Electrically conductive compositions and method of manufacture thereof

ABSTRACT

A method for manufacturing a conductive composition comprises blending a polymer precursor with a single wall carbon nanotube composition; and polymerizing the polymer precursor to form an organic polymer. The method may be advantageously used for manufacturing automotive components, computer components, and other components where electrical conductivity properties are desirable.

CROSS-REFERENCE TO RELATED APPLICATION

This application is a continuation-in part of U.S. application Ser. No.10/803,694 filed 18 Mar. 2004 now U.S. Pat. No. 7,026,432 and claimsbenefit to U.S. Provisional Patent Application Ser. No. 60/494,678 filedAug. 12, 2003, which is fully incorporated herein by reference.

BACKGROUND OF THE INVENTION

This disclosure relates to electrically conductive compositions andmethods of manufacture thereof.

Articles made from organic polymers are commonly utilized inmaterial-handling and electronic devices such as packaging film, chipcarriers, computers, printers and photocopier components whereelectrostatic dissipation or electromagnetic shielding are importantrequirements. Electrostatic dissipation (hereinafter ESD) is defined asthe transfer of electrostatic charge between bodies at differentpotentials by direct contact or by an induced electrostatic field.Electromagnetic shielding (hereinafter EM shielding) effectiveness isdefined as the ratio (in decibels) of the proportion of anelectromagnetic field incident upon the shield that is transmittedthrough it. As electronic devices become smaller and faster, theirsensitivity to electrostatic charges is increased and hence it isgenerally desirable to utilize organic polymers that have been modifiedto provide improved electrostatically dissipative properties. In asimilar manner, it is desirable to modify organic polymers so that theycan provide improved electromagnetic shielding while simultaneouslyretaining some or all of the advantageous mechanical properties of theorganic polymers.

Conductive fillers such as graphite fibers derived from pitch andpolyacrylonitrile having diameters larger than 2 micrometers are oftenincorporated into organic polymers to improve the electrical propertiesand achieve ESD and EM shielding. However, because of the large size ofthese graphite fibers, the incorporation of such fibers generally causesa decrease in the mechanical properties such as impact. Thereaccordingly remains a need in the art for conductive polymericcompositions, which while providing adequate ESD and EM shielding, canretain their mechanical properties.

BRIEF DESCRIPTION OF THE INVENTION

A method for manufacturing a conductive composition comprises blending apolymer precursor with a single wall carbon nanotube composition; andpolymerizing the polymer precursor to form an organic polymer.

DETAILED DESCRIPTION OF THE INVENTION

Disclosed herein are compositions comprising organic polymers and asingle wall carbon nanotube (SWNT) composition that are manufactured byadding the SWNTs to the polymer precursors either prior to or during theprocess of polymerization of the polymer precursor. Disclosed herein arecompositions comprising organic polymers and a single wall carbonnanotube (SWNTs) composition that have a bulk volume resistivity lessthan or equal to about 10¹² ohm-cm, while displaying impact propertiesgreater than or equal to about 5 kilojoules/square meter and a Class Asurface finish. In one embodiment, the composition has a surfaceresistivity greater than or equal to about 10⁸ ohm/square (ohm/sq) and abulk volume resistivity less than or equal to about 10¹² ohm-cm whiledisplaying impact properties greater than or equal to about 5kilojoules/square meter and a Class A surface finish. In anotherembodiment, the composition has a surface resistivity of less than orequal to about 10⁸ ohm/square (ohm/sq) and a bulk volume resistivity ofgreater than or equal to about 10⁸ ohm-cm, while displaying impactproperties greater than or equal to about 5 kilojoules/square meter anda Class A surface finish.

In one embodiment, the composition has a bulk volume resistivity of lessthan or equal to about 10¹⁰ ohm-cm while displaying impact propertiesgreater than or equal to about 5 kilojoules/square meter and a Class Asurface finish. In another embodiment, the composition has a bulk volumeresistivity of less than or equal to about 10⁸ ohm-cm while displayingimpact properties greater than or equal to about 5 kilojoules/squaremeter and a Class A surface finish. In yet another embodiment, thecomposition has a bulk volume resistivity of less than or equal to about10⁵ ohm-cm while displaying impact properties greater than or equal toabout 5 kilojoules/square meter and a Class A surface finish.

Such compositions can be advantageously utilized in computers,electronic goods, semi-conductor components, circuit boards, or the likethat need to be protected from electrostatic charges. They may also beused advantageously in automotive body panels both for interior andexterior components of automobiles that can be electrostatically paintedif desired.

In one embodiment, the SWNTs are added to the polymer precursors priorto the process of polymerization. In another embodiment, the SWNTs areadded during the process of polymerization of the polymer precursors. Inyet another embodiment, a proportion of the SWNTs are added to thepolymer precursors prior to the process of polymerization, while anotherproportion of the SWNTs are added to the polymer precursors during theprocess of polymerization. The polymer precursors, as defined herein,comprise reactive species that are monomeric, oligomeric or polymericand which can undergo additional polymerization.

The organic polymers that may be obtained from the polymerization of thepolymer precursors are thermoplastic polymers, blends of thermoplasticpolymers, or blends of thermoplastic polymers with thermosettingpolymers. The organic polymers may also be a blend of polymers,copolymers, terpolymers, interpenetrating network polymers orcombinations comprising at least one of the foregoing organic polymers.Examples of thermoplastic polymers include polyacetals, polyacrylics,polycarbonates, polyalkyds, polystyrenes, polyesters, polyamides,polyaramides, polyamideimides, polyarylates, polyarylsulfones,polyethersulfones, polyphenylene sulfides, polysulfones, polyimides,polyetherimides, polytetrafluoroethylenes, polyetherketones, polyetheretherketones, polyether ketone ketones, polybenzoxazoles,polyoxadiazoles, polybenzothiazinophenothiazines, polybenzothiazoles,polypyrazinoquinoxalines, polypyromellitimides, polyquinoxalines,polybenzimidazoles, polyoxindoles, polyoxoisoindolines,polydioxoisoindolines, polytriazines, polypyridazines, polypiperazines,polypyridines, polypiperidines, polytriazoles, polypyrazoles,polycarboranes, polyoxabicyclononanes, polydibenzofurans,polyphthalides, polyacetals, polyanhydrides, polyvinyl ethers, polyvinylthioethers, polyvinyl alcohols, polyvinyl ketones, polyvinyl halides,polyvinyl nitriles, polyvinyl esters, polysulfonates, polysulfides,polythioesters, polysulfones, polysulfonamides, polyureas,polyphosphazenes, polysilazanes, or the like, or combinations comprisingat least one of the foregoing organic polymers.

Specific examples of blends of thermoplastic polymers includeacrylonitrile-butadiene-styrene/nylon,polycarbonate/acrylonitrile-butadiene-styrene, polyphenyleneether/polystyrene, polyphenylene ether/polyamide,polycarbonate/polyester, polyphenylene ether/polyolefin, andcombinations comprising at least one of the foregoing blends ofthermoplastic polymers.

In one embodiment, an organic polymer that may be used in thecomposition is a polyarylene ether. The term poly(arylene ether) polymerincludes polyphenylene ether (PPE) and poly(arylene ether) copolymers;graft copolymers; poly(arylene ether) ether ionomers; and blockcopolymers of alkenyl aromatic compounds with poly(arylene ether)s,vinyl aromatic compounds, and poly(arylene ether), and the like; andcombinations comprising at least one of the foregoing. Poly(aryleneether) polymers per se, are polymers comprising a plurality ofstructural units of the formula (I):

wherein for each structural unit, each Q¹ is independently hydrogen,halogen, primary or secondary lower alkyl (e.g., alkyl containing up to7 carbon atoms), phenyl, haloalkyl, aminoalkyl, hydrocarbonoxy,halohydrocarbonoxy wherein at least two carbon atoms separate thehalogen and oxygen atoms, or the like; and each Q² is independentlyhydrogen, halogen, primary or secondary lower alkyl, phenyl, haloalkyl,hydrocarbonoxy, halohydrocarbonoxy wherein at least two carbon atomsseparate the halogen and oxygen atoms, or the like. Preferably, each Q¹is alkyl or phenyl, especially C₁₋₄ alkyl, and each Q² is hydrogen.

Both homopolymer and copolymer poly(arylene ether)s are included. Thepreferred homopolymers are those containing 2,6-dimethylphenylene etherunits. Suitable copolymers include random copolymers containing, forexample, such units in combination with 2,3,6-trimethyl-1,4-phenyleneether units or copolymers derived from copolymerization of2,6-dimethylphenol with 2,3,6-trimethylphenol. Also included arepoly(arylene ether) containing moieties prepared by grafting vinylmonomers or polymers such as polystyrenes, as well as coupledpoly(arylene ether) in which coupling agents such as low molecularweight polycarbonates, quinones, heterocycles and formals undergoreaction with the hydroxy groups of two poly(arylene ether) chains toproduce a higher molecular weight polymer. Poly(arylene ether)s furtherinclude combinations comprising at least one of the above.

The poly(arylene ether) has a number average molecular weight of about10,000 to about 30,000 grams/mole (g/mole) and a weight averagemolecular weight of about 30,000 to about 60,000 g/mole, as determinedby gel permeation chromatography. The poly(arylene ether) may have anintrinsic viscosity of about 0.10 to about 0.60 deciliters per gram(dl/g), as measured in chloroform at 25° C. It is also possible toutilize a high intrinsic viscosity poly(arylene ether) and a lowintrinsic viscosity poly(arylene ether) in combination. Determining anexact ratio, when two intrinsic viscosities are used, will dependsomewhat on the exact intrinsic viscosities of the poly(arylene ether)used and the ultimate physical properties that are desired.

The poly(arylene ether) is typically prepared by the oxidative couplingof at least one monohydroxyaromatic compound such as 2,6-xylenol or2,3,6-trimethylphenol. Catalyst systems are generally employed for suchcoupling; they typically contain at least one heavy metal compound suchas a copper, manganese or cobalt compound, usually in combination withvarious other materials.

Particularly useful poly(arylene ether)s for many purposes are those,which comprise molecules having at least one aminoalkyl-containing endgroup. The aminoalkyl radical is typically located in an ortho positionto the hydroxy group. Products containing such end groups may beobtained by incorporating an appropriate primary or secondary monoaminesuch as di-n-butylamine or dimethylamine as one of the constituents ofthe oxidative coupling reaction mixture. Also frequently present are4-hydroxybiphenyl end groups, typically obtained from reaction mixturesin which a by-product diphenoquinone is present, especially in acopper-halide-secondary or tertiary amine system. A substantialproportion of the polymer molecules, typically constituting as much asabout 90% by weight of the polymer, may contain at least one of theaminoalkyl-containing and 4-hydroxybiphenyl end groups.

In another embodiment, the organic polymer used in the composition maybe a polycarbonate. Polycarbonates comprising aromatic carbonate chainunits include compositions having structural units of the formula (II):

in which the R¹ groups are aromatic, aliphatic or alicyclic radicals.Preferably, R¹ is an aromatic organic radical and, more preferably, aradical of the formula (III):-A¹-Y¹-A²-  (III)wherein each of A¹ and A² is a monocyclic divalent aryl radical and Y¹is a bridging radical having zero, one, or two atoms which separate A¹from A². In an exemplary embodiment, one atom separates A¹ from A².Illustrative examples of radicals of this type are —O—, —S—, —S(O)—,—S(O₂)—, —C(O)—, methylene, cyclohexyl-methylene,2-[2,2,1]-bicycloheptylidene, ethylidene, isopropylidene,neopentylidene, cyclohexylidene, cyclopentadecylidene,cyclododecylidene, adamantylidene, or the like. The bridging radical Y¹can be a hydrocarbon group or a saturated hydrocarbon group such asmethylene, cyclohexylidene or isopropylidene.

Polycarbonates may be produced by the Schotten-Bauman interfacialreaction of the carbonate precursor with dihydroxy compounds. Typically,an aqueous base such as sodium hydroxide, potassium hydroxide, calciumhydroxide, or the like, is mixed with an organic, water immisciblesolvent such as benzene, toluene, carbon disulfide, or dichloromethane,which contains the dihydroxy compound. A phase transfer agent isgenerally used to facilitate the reaction. Molecular weight regulatorsmay be added either singly or in admixture to the reactant mixture.Branching agents, described forthwith may also be added singly or inadmixture.

Aromatic dihydroxy compound comonomers that can be employed in thedisclosure comprise those of the general formula (IV):HO-A²-OH  (IV)wherein A² is selected from divalent substituted and unsubstitutedaromatic radical.

In some embodiments, A² has the structure of formula (V):

wherein G¹ represents an aromatic group, such as phenylene, biphenylene,naphthylene, etc. E may be an alkylene or alkylidene group such asmethylene, ethylene, ethylidene, propylene, propylidene, isopropylidene,butylene, butylidene, isobutylidene, amylene, amylidene, isoamylidene,etc. and may consist of two or more alkylene or alkylidene groupsconnected by a moiety different from alkylene or alkylidene, such as anaromatic linkage; a tertiary amino linkage; an ether linkage; a carbonyllinkage; a silicon-containing linkage; or a sulfur-containing linkagesuch as sulfide, sulfoxide, sulfone, etc.; or a phosphorus-containinglinkage such as phosphinyl, phosphonyl, or the like. In addition, E maybe a cycloaliphatic group. R¹ represents hydrogen or a monovalenthydrocarbon group such as alkyl, aryl, aralkyl, alkaryl, or cycloalkyl.Y¹ may be an inorganic atom such as halogen (fluorine, bromine,chlorine, iodine); an inorganic group such as nitro; an organic groupsuch as alkenyl, allyl, or R¹ above, or an oxy group such as OR; itbeing only necessary that Y¹ be inert to and unaffected by the reactantsand reaction conditions used to prepare the polymer. The letter mrepresents any integer from and including zero through the number ofpositions on G¹ available for substitution; p represents an integer fromand including zero through the number of positions on E available forsubstitution; “t” represents an integer equal to at least one; “s” iseither zero or one; and “u” represents any integer including zero.

Suitable examples of E include cyclopentylidene, cyclohexylidene,3,3,5-trimethylcyclohexylidene, methylcyclohexylidene,2-[2.2.1]-bicycloheptylidene, neopentylidene, cyclopentadecylidene,cyclododecylidene, adamantylidene, etc.); a sulfur-containing linkage,such as sulfide, sulfoxide or sulfone; a phosphorus-containing linkage,such as phosphinyl, phosphonyl; an ether linkage; a carbonyl group; atertiary nitrogen group; or a silicon-containing linkage such as silaneor siloxy. In the aromatic dihydroxy comonomer compound (III) in whichA² is represented by formula (IV) above, when more than one Y¹substituent is present, they may be the same or different. The sameholds true for the R¹ substituent. Where s is zero in formula (IV) and uis not zero, the aromatic rings are directly joined with no interveningalkylidene or other bridge. The positions of the hydroxyl groups and Y¹on the aromatic nuclear residues G¹ can be varied in the ortho, meta, orpara positions and the groupings can be in vicinal, asymmetrical orsymmetrical relationship, where two or more ring carbon atoms of thehydrocarbon residue are substituted with Y¹ and hydroxyl groups. In someparticular embodiments, the parameters “t”, “s”, and “u” are each one;both G¹ radicals are unsubstituted phenylene radicals; and E is analkylidene group such as isopropylidene. In particular embodiments, bothG¹ radicals are p-phenylene, although both may be o- or m-phenylene orone o- or m-phenylene and the other p-phenylene. Suitable examples ofaromatic dihydroxy compounds of formula (IV) are illustrated by2,2-bis(4-hydroxyphenyl)propane (bisphenol A);2,2-bis(3-chloro-4-hydroxyphenyl)propane;2,2-bis(3-bromo-4-hydroxyphenyl)propane;2,2-bis(4-hydroxy-3-methylphenyl)propane;2,2-bis(4-hydroxy-3-isopropylphenyl)propane;2,2-bis(3-t-butyl-4-hydroxyphenyl)propane;2,2-bis(3-phenyl-4-hydroxyphenyl)propane;2,2-bis(3,5-dichloro-4-hydroxyphenyl)propane;2,2-bis(3,5-dibromo-4-hydroxyphenyl)propane;2,2-bis(3,5-dimethyl-4-hydroxyphenyl)propane;2,2-bis(3-chloro-4-hydroxy-5-methylphenyl)propane;2,2-bis(3-bromo-4-hydroxy-5-methylphenyl)propane;2,2-bis(3-chloro-4-hydroxy-5-isopropylphenyl)propane;2,2-bis(3-bromo-4-hydroxy-5-isopropylphenyl)propane;2,2-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)propane;2,2-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)propane;2,2-bis(3-chloro-5-phenyl-4-hydroxyphenyl)propane;2,2-bis(3-bromo-5-phenyl-4-hydroxyphenyl)propane;2,2-bis(3,5-disopropyl-4-hydroxyphenyl)propane;2,2-bis(3,5-di-t-butyl-4-hydroxyphenyl)propane;2,2-bis(3,5-diphenyl-4-hydroxyphenyl)propane;2,2-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)propane;2,2-bis(4-hydroxy-2,3,5,6-tetrabromophenyl)propane;2,2-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)propane;2,2-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)propane;2,2-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)propane;1,1-bis(4-hydroxyphenyl)cyclohexane;1,1-bis(3-chloro-4-hydroxyphenyl)cyclohexane;1,1-bis(3-bromo-4-hydroxyphenyl)cyclohexane;1,1-bis(4-hydroxy-3-methylphenyl)cyclohexane;1,1-bis(4-hydroxy-3-isopropylphenyl)cyclohexane;1,1-bis(3-t-butyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3-phenyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-dichloro-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-dibromo-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-dimethyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3-chloro-4-hydroxy-5-methylphenyl)cyclohexane;1,1-bis(3-bromo-4-hydroxy-5-methylphenyl)cyclohexane;1,1-bis(3-chloro-4-hydroxy-5-isopropylphenyl)cyclohexane;1,1-bis(3-bromo-4-hydroxy-5-isopropylphenyl)cyclohexane;1,1-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)cyclohexane;1,1-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3-chloro-5-phenyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3-bromo-5-phenyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-disopropyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-di-t-butyl-4-hydroxyphenyl)cyclohexane;1,1-bis(3,5-diphenyl-4-hydroxyphenyl)cyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)cyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetrabromophenyl)cyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)cyclohexane;1,1-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)cyclohexane;1,1-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)cyclohexane;1,1-bis(4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-chloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-bromo-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(4-hydroxy-3-methylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(4-hydroxy-3-isopropylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-dichloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-dibromo-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-chloro-4-hydroxy-5-methylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-bromo-4-hydroxy-5-methylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-chloro-4-hydroxy-5-isopropylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-bromo-4-hydroxy-5-isopropylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-t-butyl-5-chloro-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-bromo-5-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;bis(3-chloro-5-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3-bromo-5-phenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-disopropyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-di-t-butyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(3,5-diphenyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetrachlorophenyl)-3,3,5-trimethylcyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetrabromophenyl)-3,3,5-trimethylcyclohexane;1,1-bis(4-hydroxy-2,3,5,6-tetramethylphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(2,6-dichloro-3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;1,1-bis(2,6-dibromo-3,5-dimethyl-4-hydroxyphenyl)-3,3,5-trimethylcyclohexane;4,4′dihydroxy-1,1-biphenyl; 4,4′-dihydroxy-3,3′-dimethyl-1,1-biphenyl;4,4′-dihydroxy-3,3′-dioctyl-1,1-biphenyl; 4,4′-dihydroxydiphenylether;4,4′-dihydroxydiphenylthioether;1,3-bis(2-(4-hydroxyphenyl)-2-propyl)benzene;1,3-bis(2-(4-hydroxy-3-methylphenyl)-2-propyl)benzene;1,4-bis(2-(4-hydroxyphenyl)-2-propyl)benzene and1,4-bis(2-(4-hydroxy-3-methylphenyl)-2-propyl)benzene. The preferredaromatic dihydroxy compound is Bisphenol A (BPA).

Other bisphenol compounds that may be represented by formula (IV)include those where X is —O—, —S—, —SO— or —SO₂—. Some examples of suchbisphenol compounds are bis(hydroxyaryl)ethers such as 4,4′-dihydroxydiphenylether, 4,4′-dihydroxy-3,3′-dimethylphenyl ether, or the like;bis(hydroxy diaryl)sulfides, such as 4,4′-dihydroxy diphenyl sulfide,4,4′-dihydroxy-3,3′-dimethyl diphenyl sulfide, or the like; bis(hydroxydiaryl)sulfoxides, such as, 4,4′-dihydroxy diphenyl sulfoxides,4,4′-dihydroxy-3,3′-dimethyl diphenyl sulfoxides, or the like;bis(hydroxy diaryl)sulfones, such as 4,4′-dihydroxy diphenyl sulfone,4,4′-dihydroxy-3,3′-dimethyl diphenyl sulfone, or the like; orcombinations comprising at least one of the foregoing bisphenolcompounds.

Other bisphenol compounds that may be utilized in the polycondensationof polycarbonate are represented by the formula (VI)

wherein, R^(f), is a halogen atom of a hydrocarbon group having 1 to 10carbon atoms or a halogen substituted hydrocarbon group; n is a valuefrom 0 to 4. When n is at least 2, R^(f) may be the same or different.Examples of bisphenol compounds that may be represented by the formula(V), are resorcinol, substituted resorcinol compounds such as 3-methylresorcin, 3-ethyl resorcin, 3-propyl resorcin, 3-butyl resorcin,3-t-butyl resorcin, 3-phenyl resorcin, 3-cumyl resorcin,2,3,4,6-tetrafloro resorcin, 2,3,4,6-tetrabromo resorcin, or the like;catechol, hydroquinone, substituted hydroquinones, such as 3-methylhydroquinone, 3-ethyl hydroquinone, 3-propyl hydroquinone, 3-butylhydroquinone, 3-t-butyl hydroquinone, 3-phenyl hydroquinone, 3-cumylhydroquinone, 2,3,5,6-tetramethyl hydroquinone, 2,3,5,6-tetra-t-butylhydroquinone, 2,3,5,6-tetrafloro hydroquinone, 2,3,5,6-tetrabromohydroquinone, or the like; or combinations comprising at least one ofthe foregoing bisphenol compounds.

Bisphenol compounds such as2,2,2′,2′-tetrahydro-3,3,3′,3′-tetramethyl-1,1′-spirobi-[IH-indene]-6,6′-diolrepresented by the following formula (VI) may also be used.

The preferred bisphenol compound is bisphenol A.

Typical carbonate precursors include the carbonyl halides, for examplecarbonyl chloride (phosgene), and carbonyl bromide; thebis-haloformates, for example, the bis-haloformates of dihydric phenolssuch as bisphenol A, hydroquinone, or the like, and the bis-haloformatesof glycols such as ethylene glycol and neopentyl glycol; and the diarylcarbonates, such as diphenyl carbonate, di(tolyl) carbonate, anddi(naphthyl) carbonate. The preferred carbonate precursor for theinterfacial reaction is carbonyl chloride.

It is also possible to employ polycarbonates resulting from thepolymerization of two or more different dihydric phenols or a copolymerof a dihydric phenol with a glycol or with a hydroxy- or acid-terminatedpolyester or with a dibasic acid or with a hydroxy acid or with analiphatic diacid in the event a carbonate copolymer rather than ahomopolymer is desired for use. Generally, useful aliphatic diacids haveabout 2 to about 40 carbons. A preferred aliphatic diacid isdodecanedioic acid.

Branched polycarbonates, as well as blends of linear polycarbonate and abranched polycarbonate may also be used in the composition. The branchedpolycarbonates may be prepared by adding a branching agent duringpolymerization. These branching agents may comprise polyfunctionalorganic compounds containing at least three functional groups, which maybe hydroxyl, carboxyl, carboxylic anhydride, haloformyl, andcombinations comprising at least one of the foregoing branching agents.Specific examples include trimellitic acid, trimellitic anhydride,trimellitic trichloride, tris-p-hydroxy phenyl ethane,isatin-bis-phenol, tris-phenol TC(1,3,5-tris((p-hydroxyphenyl)isopropyl)benzene), tris-phenolPA(4(4(1,1-bis(p-hydroxyphenyl)-ethyl) α,α-dimethyl benzyl)phenol),4-chloroformyl phthalic anhydride, trimesic acid, benzophenonetetracarboxylic acid, or the like, or combinations comprising at leastone of the foregoing branching agents. The branching agents may be addedat a level of about 0.05 to about 2.0 weight percent (wt %), based uponthe total weight of the polycarbonate in a given layer.

In one embodiment, the polycarbonate may be produced by a meltpolycondensation reaction between a dihydroxy compound and a carbonicacid diester. Examples of the carbonic acid diesters that may beutilized to produce the polycarbonates are diphenyl carbonate,bis(2,4-dichlorophenyl)carbonate, bis(2,4,6-trichlorophenyl)carbonate,bis(2-cyanophenyl)carbonate, bis(o-nitrophenyl)carbonate, ditolylcarbonate, m-cresyl carbonate, dinaphthyl carbonate,bis(diphenyl)carbonate, bis(methylsalicyl)carbonate, diethyl carbonate,dimethyl carbonate, dibutyl carbonate, dicyclohexyl carbonate, or thelike, or combinations comprising at least one of the foregoing carbonicacid diesters. The preferred carbonic acid diester is diphenyl carbonateor bis (methylsalicyl)carbonate.

Preferably, the number average molecular weight of the polycarbonate isabout 3,000 to about 1,000,000 grams/mole (g/mole). Within this range,it is desirable to have a number average molecular weight of greaterthan or equal to about 10,000, preferably greater than or equal to about20,000, and more preferably greater than or equal to about 25,000g/mole. Also desirable is a number average molecular weight of less thanor equal to about 100,000, preferably less than or equal to about75,000, more preferably less than or equal to about 50,000, and mostpreferably less than or equal to about 35,000 g/mole.

Cycloaliphatic polyesters are generally prepared by reaction of a diolwith a dibasic acid or derivative. The diols useful in the preparationof the cycloaliphatic polyester polymers are straight chain, branched,or cycloaliphatic, preferably straight chain or branched alkane diols,and may contain from 2 to 12 carbon atoms.

Suitable examples of diols include ethylene glycol, propylene glycol,i.e., 1,2- and 1,3-propylene glycol; butane diol, i.e., 1,3- and1,4-butane diol; diethylene glycol, 2,2-dimethyl-1,3-propane diol,2-ethyl, 2-methyl, 1,3-propane diol, 1,3- and 1,5-pentane diol,dipropylene glycol, 2-methyl-1,5-pentane diol, 1,6-hexane diol,1,4-cyclohexane dimethanol and particularly its cis- and trans-isomers,triethylene glycol, 1,10-decane diol, and mixtures of any of theforegoing. Particularly preferred is dimethanol bicyclo octane,dimethanol decalin, a cycloaliphatic diol or chemical equivalentsthereof and particularly 1,4-cyclohexane dimethanol or its chemicalequivalents. If 1,4-cyclohexane dimethanol is to be used as the diolcomponent, it is generally preferred to use a mixture of cis- totrans-isomers in mole ratios of about 1:4 to about 4:1. Within thisrange, it is generally desired to use a mole ratio of cis- to trans-isomers of about 1:3.

The diacids useful in the preparation of the cycloaliphatic polyesterpolymers are aliphatic diacids that include carboxylic acids having twocarboxyl groups each of which are attached to a saturated carbon in asaturated ring. Suitable examples of cycloaliphatic acids includedecahydro naphthalene dicarboxylic acid, norbornene dicarboxylic acids,bicyclo octane dicarboxylic acids. Preferred cycloaliphatic diacids are1,4-cyclohexanedicarboxylic acid and trans-1,4-cyclohexanedicarboxylicacids. Linear aliphatic diacids are also useful when the polyester hasat least one monomer containing a cycloaliphatic ring. Illustrativeexamples of linear aliphatic diacids are succinic acid, adipic acid,dimethyl succinic acid, and azelaic acid. Mixtures of diacid and diolsmay also be used to make the cycloaliphatic polyesters.

Cyclohexanedicarboxylic acids and their chemical equivalents can beprepared, for example, by the hydrogenation of cycloaromatic diacids andcorresponding derivatives such as isophthalic acid, terephthalic acid ornaphthalenic acid in a suitable solvent, water or acetic acid at roomtemperature and at atmospheric pressure using suitable catalysts such asrhodium supported on a suitable carrier of carbon or alumina. They mayalso be prepared by the use of an inert liquid medium wherein an acid isat least partially soluble under reaction conditions and a catalyst ofpalladium or ruthenium in carbon or silica is used.

Typically, during hydrogenation, two or more isomers are obtainedwherein the carboxylic acid groups are in either the cis- ortrans-positions. The cis- and trans-isomers can be separated bycrystallization with or without a solvent, for example, n-heptane, or bydistillation. While the cis-isomer tends to blend better, thetrans-isomer has higher melting and crystallization temperature and isgenerally preferred. Mixtures of the cis- and trans-isomers may also beused, and preferably when such a mixture is used, the trans-isomer willpreferably comprise at least about 75 wt % and the cis-isomer willcomprise the remainder based on the total weight of cis- andtrans-isomers combined. When a mixture of isomers or more than onediacid is used, a copolyester or a mixture of two polyesters may be usedas the cycloaliphatic polyester resin.

Chemical equivalents of these diacids including esters may also be usedin the preparation of the cycloaliphatic polyesters. Suitable examplesof the chemical equivalents of the diacids are alkyl esters, e.g.,dialkyl esters, diaryl esters, anhydrides, acid chlorides, acidbromides, or the like, or combinations comprising at least one of theforegoing chemical equivalents. The preferred chemical equivalentscomprise the dialkyl esters of the cycloaliphatic diacids, and the mostpreferred chemical equivalent comprises the dimethyl ester of the acid,particularly dimethyl-trans-1,4-cyclohexanedicarboxylate.

Dimethyl-1,4-cyclohexanedicarboxylate can be obtained by ringhydrogenation of dimethylterephthalate, wherein two isomers having thecarboxylic acid groups in the cis- and trans-positions are obtained. Theisomers can be separated, the trans-isomer being especially preferred.Mixtures of the isomers may also be used as detailed above.

The polyester polymers are generally obtained through the condensationor ester interchange polymerization of the diol or diol chemicalequivalent component with the diacid or diacid chemical equivalentcomponent and having recurring units of the formula (VIII):

wherein R³ represents an aryl, alkyl or cycloalkyl radical which is theresidue of a straight chain, branched, or cycloaliphatic alkane diol orchemical equivalents thereof; and R⁴ is an aryl, alkyl or acycloaliphatic radical which is the decarboxylated residue derived froma diacid, with the proviso that at least one of R³ or R⁴ is a cycloalkylgroup. The aryl radicals may be substituted aryl radicals if desired.

A preferred cycloaliphatic polyester ispoly(1,4-cyclohexane-dimethanol-1,4-cyclohexanedicarboxylate) havingrecurring units of formula (IX)

wherein in the formula (VIII), R³ is a cyclohexane ring, and wherein R⁴is a cyclohexane ring derived from cyclohexanedicarboxylate or achemical equivalent thereof and is selected from the cis- ortrans-isomer or a mixture of cis- and trans-isomers thereof.Cycloaliphatic polyester polymers can be generally made in the presenceof a suitable catalyst such as a tetra(2-ethyl hexyl)titanate, in asuitable amount, typically about 50 to 400 ppm of titanium based uponthe total weight of the final product.Poly(1,4-cyclohexanedimethanol-1,4-cyclohexanedicarboxylate) generallyforms a suitable blend with the polycarbonate.

Preferably, the number average molecular weight of thecopolyestercarbonates or the polyesters is about 3,000 to about1,000,000 g/mole. Within this range, it is desirable to have a numberaverage molecular weight of greater than or equal to about 10,000,preferably greater than or equal to about 20,000, and more preferablygreater than or equal to about 25,000 g/mole. Also desirable is a numberaverage molecular weight of less than or equal to about 100,000,preferably less than or equal to about 75,000, more preferably less thanor equal to about 50,000, and most preferably less than or equal toabout 35,000 g/mole.

Another preferred polyester is a polyarylate. Polyarylates generallyrefers to polyesters of aromatic dicarboxylic acids and bisphenols.Polyarylate copolymers that include carbonate linkages in addition tothe aryl ester linkages, are termed polyester-carbonates, and may alsobe advantageously utilized in the mixtures. The polyarylates can beprepared in solution or by the melt polymerization of aromaticdicarboxylic acids or their ester forming derivatives with bisphenols ortheir derivatives.

In general, it is preferred for the polyarylates to comprise at leastone diphenol residue in combination with at least one aromaticdicarboxylic acid residue. The preferred diphenol residue, illustratedin formula (X), is derived from a 1,3-dihydroxybenzene moiety, referredto throughout this specification as resorcinol or resorcinol moiety.Resorcinol or resorcinol moieties include both unsubstituted1,3-dihydroxybenzene and substituted 1,3-dihydroxybenzenes.

In formula (X), R is at least one of C₁₋₁₂ alkyl or halogen, and n is 0to 3. Suitable dicarboxylic acid residues include aromatic dicarboxylicacid residues derived from monocyclic moieties, preferably isophthalicacid, terephthalic acid, or mixtures of isophthalic and terephthalicacids, or from polycyclic moieties such as diphenyl dicarboxylic acid,diphenylether dicarboxylic acid, and naphthalene-2,6-dicarboxylic acid,and the like, as well as combinations comprising at least one of theforegoing polycyclic moieties. The preferred polycyclic moiety isnaphthalene-2,6-dicarboxylic acid.

Preferably, the aromatic dicarboxylic acid residues are derived frommixtures of isophthalic and/or terephthalic acids as generallyillustrated in formula (XI).

Therefore, in one embodiment the polyarylates comprise resorcinolarylate polyesters as illustrated in formula (XII)

wherein R is at least one of C₁₋₁₂ alkyl or halogen, n is 0 to 3, and mis at least about 8. It is preferred for R to be hydrogen. Preferably, nis zero and m is about 10 and about 300. The molar ratio of isophthalateto terephthalate is about 0.25:1 to about 4.0:1.

In another embodiment, the polyarylate comprises thermally stableresorcinol arylate polyesters that have polycyclic aromatic radicals asshown in formula (XIII)

wherein R is at least one of C₁₋₁₂ alkyl or halogen, n is 0 to 3, and mis at least about 8.

In another embodiment, the polyarylates are copolymerized to form blockcopolyestercarbonates, which comprise carbonate and arylate blocks. Theyinclude polymers comprising structural units of the formula (XIV)

wherein each R¹ is independently halogen or C₁₋₁₂ alkyl, m is at least1, p is about 0 to about 3, each R² is independently a divalent organicradical, and n is at least about 4. Preferably n is at least about 10,more preferably at least about 20 and most preferably about 30 to about150. Preferably m is at least about 3, more preferably at least about 10and most preferably about 20 to about 200. In an exemplary embodiment mis present in an amount of about 20 and 50.

It is generally desirable for the weight average molecular weight of thepolyarylate to be about 500 to about 1,000,000 grams/mole (g/mole). Inone embodiment, the polyarylate has a weight average molecular weight ofabout 10,000 to about 200,000 g/mole. In another embodiment, thepolyarylate has a weight average molecular weight of about 30,000 toabout 150,000 g/mole. In yet another embodiment, the polyarylate has aweight average molecular weight of about 50,000 to about 120,000 g/mole.An exemplary molecular weight for the polyarylate utilized in the caplayer is 60,000 and 120,000 g/mole.

In one embodiment, the polymer precursor comprises an ethylenicallyunsaturated group. The ethylenically unsaturated groups used can be anyethylenically unsaturated functional group capable of polymerization.Suitable ethylenically unsaturated functionality includesfunctionalization that can be polymerized through radical polymerizationor cationic polymerization. Specific examples of suitable ethylenicunsaturation are groups containing acrylate, methacrylate, vinylaromatic polymers such as styrene; vinylether, vinyl ester,N-substituted acrylamide, N-vinyl amide, maleate esters, fumarateesters, and the like. Preferably, the ethylenic unsaturation is providedby a group containing acrylate, methacrylate, or styrene functionality,and most preferably styrene.

The vinyl aromatic resins are preferably derived from polymer precursorsthat contain at least 25% by weight of structural units derived from amonomer of the formula (XV):

wherein R⁵ is hydrogen, lower alkyl or halogen; Z¹ is vinyl, halogen orlower alkyl; and p is from 0 to about 5. These polymers includehomopolymers of styrene, chlorostyrene and vinyltoluene, randomcopolymers of styrene with one or more monomers illustrated byacrylonitrile, butadiene, alpha -methylstyrene, ethylvinylbenzene,divinylbenzene and maleic anhydride, and rubber-modified polystyrenescomprising blends and grafts, wherein the rubber is a polybutadiene or arubbery copolymer of about 98-70% styrene and about 2-30% diene monomer.Polystyrenes are miscible with polyphenylene ether in all proportions,and any such blend may contain polystyrene in amounts of about 5-95% andmost often about 25-75%, based on the total weight of the polymers.

In yet another embodiment, polyimides may be used as the organicpolymers in the composition. Useful thermoplastic polyimides have thegeneral formula (XVI)

wherein “a” is greater than or equal to about 1, preferably greater thanor equal to about 10, and more preferably greater than or equal to about1000; and wherein V is a tetravalent linker without limitation, as longas the linker does not impede synthesis or use of the polyimide.Suitable linkers include (a) substituted or unsubstituted, saturated,unsaturated or aromatic monocyclic and polycyclic groups having about 5to about 50 carbon atoms, (b) substituted or unsubstituted, linear orbranched, saturated or unsaturated alkyl groups having 1 to about 30carbon atoms; or combinations thereof. Suitable substitutions and/orlinkers include, but are not limited to, ethers, epoxides, amides,esters, and combinations thereof. Preferred linkers include but are notlimited to tetravalent aromatic radicals of formula (XVII), such as

wherein W is a divalent moiety selected from the group consisting of—O—, —S—, —C(O)—, —SO₂—, —SO—, —C_(y)H_(2y)— (y being an integer from 1to 5), and halogenated derivatives thereof, including perfluoroalkylenegroups, or a group of the formula —O-Z-O— wherein the divalent bonds ofthe —O— or the —O-Z-O— group are in the 3,3′,3,4′,4,3′, or the 4,4′positions, and wherein Z includes, but is not limited, to divalentradicals of formula (XVIII).

R in formula (XVI) includes substituted or unsubstituted divalentorganic radicals such as (a) aromatic hydrocarbon radicals having about6 to about 20 carbon atoms and halogenated derivatives thereof; (b)straight or branched chain alkylene radicals having about 2 to about 20carbon atoms; (c) cycloalkylene radicals having about 3 to about 20carbon atoms, or (d) divalent radicals of the general formula (XIX)

wherein Q includes a divalent moiety selected from the group consistingof —O—, —S—, —C(O)—, —SO₂—, —SO—, —C_(y)H_(2y)— (y being an integer from1 to 5), and halogenated derivatives thereof, includingperfluoroalkylene groups.

Preferred classes of polyimides include polyamidimides andpolyetherimides, particularly those polyetherimides that are meltprocessable.

Preferred polyetherimide polymers comprise more than 1, typically about10 to about 1000 or more, and more preferably about 10 to about 500structural units, of the formula (XX)

wherein T is —O— or a group of the formula —O-Z-O— wherein the divalentbonds of the —O— or the —O-Z-O— group are in the 3,3′,3,4′,4,3′, or the4,4′ positions, and wherein Z includes, but is not limited, to divalentradicals of formula (XVIII) as defined above.

In one embodiment, the polyetherimide may be a copolymer, which, inaddition to the etherimide units described above, further containspolyimide structural units of the formula (XXI)

wherein R is as previously defined for formula (XVI) and M includes, butis not limited to, radicals of formula (XXII).

The polyetherimide can be prepared by any of the methods including thereaction of an aromatic bis(ether anhydride) of the formula (XXIII)

with an organic diamine of the formula (XIV)H₂N—R—NH₂  (XXIV)wherein T and R are defined as described above in formulas (XVI) and(XX).

Illustrative examples of aromatic bis(ether anhydride)s of formula(XXIII) include 2,2-bis[4-(3,4-dicarboxyphenoxy)phenyl]propanedianhydride; 4,4′-bis(3,4-dicarboxyphenoxy)diphenyl ether dianhydride;4,4′-bis(3,4-dicarboxyphenoxy)diphenyl sulfide dianhydride;4,4′-bis(3,4-dicarboxyphenoxy)benzophenone dianhydride;4,4′-bis(3,4-dicarboxyphenoxy)diphenyl sulfone dianhydride;2,2-bis[4-(2,3-dicarboxyphenoxy)phenyl]propane dianhydride;4,4′-bis(2,3-dicarboxyphenoxy)diphenyl ether dianhydride;4,4′-bis(2,3-dicarboxyphenoxy)diphenyl sulfide dianhydride;4,4′-bis(2,3-dicarboxyphenoxy)benzophenone dianhydride;4,4′-bis(2,3-dicarboxyphenoxy)diphenyl sulfone dianhydride;4-(2,3-dicarboxyphenoxy)-4′-(3,4-dicarboxyphenoxy)diphenyl-2,2-propanedianhydride; 4-(2,3-dicarboxyphenoxy)-4′-(3,4-dicarboxyphenoxy)diphenylether dianhydride;4-(2,3-dicarboxyphenoxy)-4′-(3,4-dicarboxyphenoxy)diphenyl sulfidedianhydride;4-(2,3-dicarboxyphenoxy)-4′-(3,4-dicarboxyphenoxy)benzophenonedianhydride and4-(2,3-dicarboxyphenoxy)-4′-(3,4-dicarboxyphenoxy)diphenyl sulfonedianhydride, as well as various mixtures thereof.

The bis(ether anhydride)s can be prepared by the hydrolysis, followed bydehydration, of the reaction product of a nitro substituted phenyldinitrile with a metal salt of dihydric phenol compound in the presenceof a dipolar, aprotic solvent. A preferred class of aromatic bis(etheranhydride)s included by formula (XXIII) above includes, but is notlimited to, compounds wherein T is of the formula (XXV)

and the ether linkages, for example, are preferably in the3,3′,3,4′,4,3′, or 4,4′ positions, and mixtures thereof, and where Q isas defined above.

Any diamino compound may be employed in the preparation of thepolyimides and/or polyetherimides. Examples of suitable compounds areethylenediamine, propylenediamine, trimethylenediamine,diethylenetriamine, triethylenetertramine, hexamethylenediamine,heptamethylenediamine, octamethylenediamine, nonamethylenediamine,decamethylenediamine, 1,12-dodecanediamine, 1,18-octadecanediamine,3-methylheptamethylenediamine, 4,4-dimethylheptamethylenediamine,4-methylnonamethylenediamine, 5-methylnonamethylenediamine,2,5-dimethylhexamethylenediamine, 2,5-dimethylheptamethylenediamine,2,2-dimethylpropylenediamine, N-methyl-bis (3-aminopropyl)amine,3-methoxyhexamethylenediamine, 1,2-bis(3-aminopropoxy)ethane,bis(3-aminopropyl)sulfide, 1,4-cyclohexanediamine,bis-(4-aminocyclohexyl)methane, m-phenylenediamine, p-phenylenediamine,2,4-diaminotoluene, 2,6-diaminotoluene, m-xylylenediamine,p-xylylenediamine, 2-methyl-4,6-diethyl-1,3-phenylene-diamine,5-methyl-4,6-diethyl-1,3-phenylene-diamine, benzidine,3,3′-dimethylbenzidine, 3,3′-dimethoxybenzidine, 1,5-diaminonaphthalene,bis(4-aminophenyl)methane, bis(2-chloro-4-amino-3,5-diethylphenyl)methane, bis(4-aminophenyl)propane,2,4-bis(b-amino-t-butyl) toluene, bis(p-b-amino-t-butylphenyl)ether,bis(p-b-methyl-o-aminophenyl) benzene,bis(p-b-methyl-o-aminopentyl)benzene, 1,3-diamino-4-isopropylbenzene,bis(4-aminophenyl)sulfide, bis(4-aminophenyl)sulfone,bis(4-aminophenyl)ether and 1,3-bis(3-aminopropyl)tetramethyldisiloxane.Mixtures of these compounds may also be present. The preferred diaminocompounds are aromatic diamines, especially m- and p-phenylenediamineand mixtures thereof.

In an exemplary embodiment, the polyetherimide resin comprisesstructural units according to formula (XX) wherein each R isindependently p-phenylene or m-phenylene or a mixture thereof and T is adivalent radical of the formula (XXVI)

In general, the reactions can be carried out employing solvents such aso-dichlorobenzene, m-cresol/toluene, or the like, to effect a reactionbetween the anhydride of formula (XVIII) and the diamine of formula(XIX), at temperatures of about 100° C. to about 250° C. Alternatively,the polyetherimide can be prepared by melt polymerization of aromaticbis(ether anhydride)s of formula (XVIII) and diamines of formula (XIX)by heating a mixture of the starting materials to elevated temperatureswith concurrent stirring. Generally, melt polymerizations employtemperatures of about 200° C. to about 400° C. Chain stoppers andbranching agents may also be employed in the reaction. Whenpolyetherimide/polyimide copolymers are employed, a dianhydride, such aspyromellitic anhydride, is used in combination with the bis(etheranhydride). The polyetherimide polymers can optionally be prepared fromreaction of an aromatic bis(ether anhydride) with an organic diamine inwhich the diamine is present in the reaction mixture at no more thanabout 0.2 molar excess, and preferably less than about 0.2 molar excess.Under such conditions the polyetherimide resin has less than about 15microequivalents per gram (μeq/g) acid titratable groups, and preferablyless than about 10 μeq/g acid titratable groups, as shown by titrationwith chloroform solution with a solution of 33 weight percent (wt %)hydrobromic acid in glacial acetic acid. Acid-titratable groups areessentially due to amine end-groups in the polyetherimide resin.

Generally, useful polyetherimides have a melt index of about 0.1 toabout 10 grams per minute (g/min), as measured by American Society forTesting Materials (ASTM) D1238 at 295° C., using a 6.6 kilogram (kg)weight. In a preferred embodiment, the polyetherimide resin has a weightaverage molecular weight (Mw) of about 10,000 to about 150,000 grams permole (g/mole), as measured by gel permeation chromatography, using apolystyrene standard. Such polyetherimide polymers typically have anintrinsic viscosity greater than about 0.2 deciliters per gram (dl/g),preferably about 0.35 to about 0.7 dl/g measured in m-cresol at 25° C.

In yet another embodiment, polyamides may be used as the organicpolymers in the composition. Polyamides are generally derived from thepolymerization of organic lactams having from 4 to 12 carbon atoms.Preferred lactams are represented by the formula (XXVII)

wherein n is about 3 to about 11. A highly preferred lactam isepsilon-caprolactam having n equal to 5.

Polyamides may also be synthesized from amino acids having from 4 to 12carbon atoms. Preferred amino acids are represented by the formula(XXVIII)

wherein n is about 3 to about 11. A highly preferred amino acid isepsilon-aminocaproic acid with n equal to 5.

Polyamides may also be polymerized from aliphatic dicarboxylic acidshaving from 4 to 12 carbon atoms and aliphatic diamines having from 2 to12 carbon atoms. Suitable and preferred aliphatic dicarboxylic acids arethe same as those described above for the synthesis of polyesters.Preferred aliphatic diamines are represented by the formula (XXIX)H₂N—(CH₂)_(n)—NH₂  (XXIX)wherein n is about 2 to about 12. A highly preferred aliphatic diamineis hexamethylenediamine (H₂N(CH₂)₆NH₂). It is preferred that the molarratio of the dicarboxylic acid to the diamine be about 0.66 to about1.5. Within this range it is generally desirable to have the molar ratiobe greater than or equal to about 0.81, preferably greater than or equalto about 0.96. Also desirable within this range is an amount of lessthan or equal to about 1.22, preferably less than or equal to about1.04. The preferred polyamides are nylon 6, nylon 6,6, nylon 4,6, nylon6, 12, nylon 10, or the like, or combinations comprising at least one ofthe foregoing nylons.

Synthesis of polyamideesters may also be accomplished from aliphaticlactones having from 4 to 12 carbon atoms and aliphatic lactams havingfrom 4 to 12 carbon atoms. The aliphatic lactones are the same as thosedescribed above for polyester synthesis, and the aliphatic lactams arethe same as those described above for the synthesis of polyamides. Theratio of aliphatic lactone to aliphatic lactam may vary widely dependingon the desired composition of the final copolymer, as well as therelative reactivity of the lactone and the lactam. A presently preferredinitial molar ratio of aliphatic lactam to aliphatic lactone is about0.5 to about 4. Within this range a molar ratio of greater than or equalto about 1 is desirable. Also desirable is a molar ratio of less than orequal to about 2.

The composition may further comprise a catalyst or an initiator.Generally, any known catalyst or initiator suitable for thecorresponding thermal polymerization may be used. Alternatively, thepolymerization may be conducted without a catalyst or initiator. Forexample, in the synthesis of polyamides from aliphatic dicarboxylicacids and aliphatic diamines, no catalyst is required.

For the synthesis of polyamides from lactams, suitable catalysts includewater and the omega-amino acids corresponding to the ring-opened(hydrolyzed) lactam used in the synthesis. Other suitable catalystsinclude metallic aluminum alkylates (MAl(OR)₃H; wherein M is an alkalimetal or alkaline earth metal, and R is C₁-C₁₂ alkyl), sodiumdihydrobis(2-methoxyethoxy)aluminate, lithiumdihydrobis(tert-butoxy)aluminate, aluminum alkylates (Al(OR)₂R; whereinR is C₁-C₁₂ alkyl), N-sodium caprolactam, magnesium chloride or bromidesalt of epsilon-caprolactam (MgXC₆H₁₀NO, X═Br or Cl), dialkoxy aluminumhydride. Suitable initiators include isophthaloybiscaprolactam,N-acetalcaprolactam, isocyanate epsilon-caprolactam adducts, alcohols(ROH; wherein R is C₁-C₁₂ alkyl), diols (HO—R—OH; wherein R is R isC₁-C₁₂ alkylene), omega-aminocaproic acids, and sodium methoxide.

For the synthesis of polyamideesters from lactones and lactams, suitablecatalysts include metal hydride compounds, such as a lithium aluminumhydride catalysts having the formula LiAl(H)_(x)(R¹)_(y), where x isabout 1 to about 4, y is about 0 to about 3, x+y is equal to 4, and R¹is selected from the group consisting of C₁-C₁₂ alkyl and C₁-C₁₂ alkoxy;highly preferred catalysts include LiAl(H)(OR²)₃, wherein R² is selectedfrom the group consisting of C₁-C₈ alkyl; an especially preferredcatalyst is LiAl(H)(OC(CH₃)₃)₃. Other suitable catalysts and initiatorsinclude those described above for the polymerization ofpoly(epsilon-caprolactam) and poly(epsilon-caprolactone).

A preferred type of polyamide is one obtained by the reaction of a firstpolyamide and a polymeric material selected from the group consisting ofa second polyamide, poly(arylene ether), poly(alkenyl aromatic)homopolymer, rubber modified poly(alkenyl aromatic) resin,acrylonitrile-butadiene-styrene (ABS) graft copolymers, block copolymer,and combinations comprising two or more of the foregoing. The firstpolyamide comprises repeating units having formula (XXX)

wherein R¹ is a branched or unbranched alkyl group having nine carbons.R¹ is preferably 1,9-nonane and/or 2-methyl-1,8-octane. Polyamide resinsare characterized by the presence of an amide group (—C(O)NH—) which isthe condensation product of a carboxylic acid and an amine. The firstpolyamide is typically made by reacting one or more diamines comprisinga nine carbon alkyl moiety with terephthalic acid (1,4-dicarboxybenzene). When employing more than one diamine the ratio of the diaminescan affect some of the physical properties of the resulting polymer suchas the melt temperature. The ratio of diamine to dicarboxylic acid istypically equimolar although excesses of one or the other may be used todetermine the end group functionality. In addition the reaction canfurther include monoamines and monocarboxylic acids which function aschain stoppers and determine, at least in part, the end groupfunctionality. In some embodiments it is preferable to have an amine endgroup content of greater than or equal to about 30 meq/g, and morepreferably greater than or equal to about 40 meq/g.

The second polyamide comprises repeating units having formula (XXXI)and/or formula (XXXII)

wherein R² is a branched or unbranched alkyl group having four to sevencarbons and R³is an aromatic group having six carbons or a branched orunbranched alkyl group having four to seven carbons. R² is preferably1,6-hexane in formula XXXI and 1,5-pentane in formula XXXII. R³ ispreferably 1,4-butane.

The first polyamide has better dimensional stability, temperatureresistance, resistance to moisture uptake, abrasion resistance andchemical resistance compared to other polyamides. Hence, compositionscomprising the first polyamide exhibit these same improved propertieswhen compared to comparable compositions containing other polyamides inplace of the first polyamide. In some embodiments the combination of thefirst and second polyamide improves the compatibility of the polyamidephase with other phases, such as poly(arylene ether), in multiphasiccompositions thereby improving the impact resistance. Without beingbound by theory it is believed that the second polyamide increases theamount of available terminal amino groups. The terminal amino groupscan, in some instances, react with components of other phases or befunctionalized to react with other phases, thereby improving thecompatibility.

The organic polymer is generally present in amounts of about 5 to about99.999 weight percent (wt %) in the composition. Within this range, itis generally desirable use the organic polymer or the polymeric blend inan amount of greater than or equal to about 10 wt %, preferably greateror equal to about 30 wt %, and more preferably greater than or equal toabout 50 wt % of the total weight of the composition. The organicpolymers or polymeric blends are furthermore generally used in amountsless than or equal to about 99.99 wt %, preferably less than or equal toabout 99.5 wt %, more preferably less than or equal to about 99.3 wt %of the total weight of the composition

SWNTs used in the composition may be produced by laser-evaporation ofgraphite, carbon arc synthesis or the high-pressure carbon monoxideconversion process (HIPCO) process. These SWNTs generally have a singlewall comprising a graphene sheet with outer diameters of about 0.7 toabout 2.4 nanometers (nm). SWNTs having aspect ratios of greater than orequal to about 5, preferably greater than or equal to about 100, morepreferably greater than or equal to about 1000 are generally utilized inthe compositions. While the SWNTs are generally closed structures havinghemispherical caps at each end of the respective tubes, it is envisionedthat SWNTs having a single open end or both open ends may also be used.The SWNTs generally comprise a central portion, which is hollow, but maybe filled with amorphous carbon.

In an exemplary embodiment, the purpose of dispersion of the SWNTs in anorganic polymer is to disentangle the SWNTs so as to obtain an effectiveaspect ratio that is as close to the aspect ratio of the SWNT aspossible. The ratio of the effective aspect ratio to the aspect ratio isa measure of the effectiveness of dispersion. The effective aspect ratiois a value that is twice the radius of gyration of a single SWNT dividedby the outer diameter of the respective individual nanotube. It isgenerally desirable for the average value of ratio of the effectiveaspect ratio to the aspect ratio to be greater than or equal to about0.5, preferably greater than or equal to about 0.75, and more preferablygreater than or equal to about 0.90, as measured in a electronmicrograph at a magnification of greater than or equal to about 10,000.

In one embodiment, the SWNTs may exist in the form ofrope-like-aggregates. These aggregates are commonly termed “ropes” andare formed as a result of Van der Waal's forces between the individualSWNTs. The individual nanotubes in the ropes may slide against oneanother and rearrange themselves within the rope in order to minimizethe free energy. Ropes generally having between 10 and 10⁵ nanotubes maybe used in the compositions. Within this range, it is generallydesirable to have ropes having greater than or equal to about 100,preferably greater than or equal to about 500 nanotubes. Also desirable,are ropes having less than or equal to about 10⁴ nanotubes, preferablyless than or equal to about 5,000 nanotubes.

In yet another embodiment, it is desirable for the SWNT ropes to connecteach other in the form of branches after dispersion. This results in asharing of the ropes between the branches of the SWNT networks to form a3-diminsional network in the organic polymer matrix. A distance of about10 nm to about 10 micrometers may separate the branching points in thistype of network. It is generally desirable for the SWNTs to have aninherent thermal conductivity of at least 2000 Watts per meter Kelvin(W/m-K) and for the SWNT ropes to have an inherent electricalconductivity of 10⁴ Siemens/centimeter (S/cm). It is also generallydesirable for the SWNTs to have a tensile strength of at least 80gigapascals (GPa) and a stiffness of at least about 0.5 tarapascals(TPa).

In another embodiment, the SWNTs may comprise a mixture of metallicnanotubes and semi-conducting nanotubes. Metallic nanotubes are thosethat display electrical characteristics similar to metals, while thesemi-conducting nanotubes are those, which are electricallysemi-conducting. In general the manner in which the graphene sheet isrolled up produces nanotubes of various helical structures. Zigzag andarmchair nanotubes constitute two possible confirmations. In order tominimize the quantity of SWNTs utilized in the composition, it isgenerally desirable to have the composition comprise as large a fractionof metallic SWNTs. It is generally desirable for the SWNTs used in thecomposition to comprise metallic nanotubes in an amount of greater thanor equal to about 1 wt %, preferably greater than or equal to about 20wt %, more preferably greater than or equal to about 30 wt %, even morepreferably greater than or equal to about 50 wt %, and most preferablygreater than or equal to about 99.9 wt % of the total weight of theSWNTs. In certain situations, it is generally desirable for the SWNTsused in the composition to comprise semi-conducting nanotubes in anamount of greater than or equal to about 1 wt %, preferably greater thanor equal to about 20 wt %, more preferably greater than or equal toabout 30 wt %, even more preferably greater than or equal to about 50 wt%, and most preferably greater than or equal to about 99.9 wt % of thetotal weight of the SWNTs.

SWNTs are generally used in amounts of about 0.001 to about 80 wt % ofthe total weight of the composition when desirable. Within this range,SWNTs are generally used in amounts greater than or equal to about 0.25wt %, preferably greater or equal to about 0.5 wt %, more preferablygreater than or equal to about 1 wt % of the total weight of thecomposition. SWNTs are furthermore generally used in amounts less thanor equal to about 30 wt %, preferably less than or equal to about 10 wt%, more preferably less than or equal to about 5 wt % of the totalweight of the composition.

In one embodiment, the SWNTs may contain production related impurities.Production related impurities present in SWNTs as defined herein arethose impurities, which are produced during processes substantiallyrelated to the production of SWNTs. As stated above, SWNTs are producedin processes such as, for example, laser ablation, chemical vapordeposition, carbon arc, high-pressure carbon monoxide conversionprocesses, or the like. Production related impurities are thoseimpurities that are either formed naturally or formed deliberatelyduring the production of SWNTs in the aforementioned processes orsimilar manufacturing processes. A suitable example of a productionrelated impurity that is formed naturally are catalyst particles used inthe production of the SWNTs. A suitable example of a production relatedimpurity that is formed deliberately is a dangling bond formed on thesurface of the SWNT by the deliberate addition of a small amount of anoxidizing agent during the manufacturing process.

Production related impurities include for example, carbonaceous reactionby-products such as defective SWNTs, multiwall carbon nanotubes,branched or coiled multiwall carbon nanotubes, amorphous carbon, soot,nano-onions, nanohoms, coke, or the like; catalytic residues from thecatalysts utilized in the production process such as metals, metaloxides, metal carbides, metal nitrides or the like, or combinationscomprising at least one of the foregoing reaction byproducts. A processthat is substantially related to the production of SWNTs is one in whichthe fraction of SWNTs is larger when compared with any other fraction ofproduction related impurities. In order for a process to besubstantially related to the production of SWNTs, the fraction of SWNTswould have to be greater than a fraction of any one of the above listedreaction byproducts or catalytic residues. For example, the fraction ofSWNTs would have to be greater than the fraction of multiwall nanotubes,or the fraction of soot, or the fraction of carbon black. The fractionof SWNTs would not have to be greater than the sums of the fractions ofany combination of production related impurities for the process to beconsidered substantially directed to the production of SWNTs.

In general, the SWNTs used in the composition may comprise an amount ofabout 0.1 to about 80 wt % impurities. Within this range, the SWNTs mayhave an impurity content greater than or equal to about 3, preferablygreater than or equal to about 7, and more preferably greater than orequal to about 8 wt %, of the total weight of the SWNTs. Also desirablewithin this range, is an impurity content of less than of equal to about50, preferably less than or equal to about 45, and more preferably lessthan or equal to about 40 wt % of the total weight of the SWNTs.

In one embodiment, the SWNTs used in the composition may comprise anamount of about 0.1 to about 50 wt % catalytic residues. Within thisrange, the SWNTs may have a catalytic residue content greater than orequal to about 3, preferably greater than or equal to about 7, and morepreferably greater than or equal to about 8 wt %, of the total weight ofthe SWNTs. Also desirable within this range, is a catalytic residuecontent of less than of equal to about 50, preferably less than or equalto about 45, and more preferably less than or equal to about 40 wt % ofthe total weight of the SWNTs.

Other carbon nanotubes such as multiwall carbon nanotubes (MWNTs) andVGCF may also be added to the compositions during the polymerization ofthe polymeric precursor. The MWNTs and VGCF that are added to thecomposition are not considered impurities since these are not producedduring the production of the SWNTs. MWNTs derived from processes such aslaser ablation and carbon arc synthesis, which is not directed at theproduction of SWNTs, may also be used in the compositions. MWNTs have atleast two graphene layers bound around an inner hollow core.Hemispherical caps generally close both ends of the MWNTs, but it maydesirable to use MWNTs having only one hemispherical cap or MWNTs, whichare devoid of both caps. MWNTs generally have diameters of about 2 toabout 50 nm. Within this range, it is generally desirable to use MWNTshaving diameters less than or equal to about 40, preferably less than orequal to about 30, and more preferably less than or equal to about 20nm. When MWNTs are used, it is preferred to have an average aspect ratiogreater than or equal to about 5, preferably greater than or equal toabout 100, more preferably greater than or equal to about 1000.

MWNTs are generally used in amounts of about 0.001 to about 50 wt % ofthe total weight of the composition when desirable. Within this range,MWNTs are generally used in amounts greater than or equal to about 0.25wt %, preferably greater or equal to about 0.5 wt %, more preferablygreater than or equal to about 1 wt % of the total weight of thecomposition. MWNTs are furthermore generally used in amounts less thanor equal to about 30 wt %, preferably less than or equal to about 10 wt%, more preferably less than or equal to about 5 wt % of the totalweight of the composition.

Other conductive fillers such as vapor grown carbon fibers, carbonblack, conductive metallic fillers, solid non-metallic, conductivefillers, or the like, or combinations comprising at least one of theforegoing may optionally be used in the compositions. Vapor grown carbonfibers or small graphitic or partially graphitic carbon fibers, alsoreferred to as vapor grown carbon fibers (VGCF), having diameters ofabout 3.5 to about 2000 nanometers (nm) and an aspect ratio greater thanor equal to about 5 may also be used. When VGCF are used, diameters ofabout 3.5 to about 500 nm are preferred, with diameters of about 3.5 toabout 100 nm being more preferred, and diameters of about 3.5 to about50 nm most preferred. It is also preferable to have average aspectratios greater than or equal to about 100 and more preferably greaterthan or equal to about 1000.

VGCF are generally used in amounts of about 0.001 to about 50 wt % ofthe total weight of the composition when desirable. Within this range,VGCF are generally used in amounts greater than or equal to about 0.25wt %, preferably greater or equal to about 0.5 wt %, more preferablygreater than or equal to about 1 wt % of the total weight of thecomposition. VGCF are furthermore generally used in amounts less than orequal to about 30 wt %, preferably less than or equal to about 10 wt %,more preferably less than or equal to about 5 wt % of the total weightof the composition.

Both the SWNTs and the other carbon nanotubes utilized in thecomposition may also be derivatized with functional groups to improvecompatibility and facilitate the mixing with the organic polymer. TheSWNTs and the other carbon nanotubes may be functionalized on either thegraphene sheet constituting the sidewall, a hemispherical cap or on boththe side wall as well as the hemispherical endcap. Functionalized SWNTsand the other carbon nanotubes are those having the formula (XXXIII)[C_(n)H_(L)

R_(m)  (XXXIII)wherein n is an integer, L is a number less than 0.1 n, m is a numberless than 0.5 n, and wherein each of R is the same and is selected from—SO₃H, —NH₂, —OH, —C(OH)R′, —CHO, —CN, —C(O)Cl, —C(O)SH, —C(O)OR′, —SR′,—SiR₃′, —Si(OR′)_(y)R′_((3-y)), —R″, —AlR₂′, AlR₂′, halide,ethylenically unsaturated functionalities, epoxide functionalities, orthe like, wherein y is an integer equal to or less than 3, R′ ishydrogen, alkyl, aryl, cycloalkyl, araalkyl, cycloaryl,poly(alkylether), or the like and R″ is fluoroalkyl, fluoroaryl,fluorocycloalkyl, fluoroaralkyl, cycloaryl, or the like. The carbonatoms, C_(n), are surface carbons of a carbon nanotube. In both,uniformly and non-uniformly substituted SWNTs and other carbonnanotubes, the surface atoms C_(n) are reacted.

Non-uniformly substituted SWNTs and other carbon nanotubes may also beused in the composition. These include compositions of the formula (I)shown above wherein n, L, m, R and the SWNT itself are as defined above,provided that each of R does not contain oxygen, or, if each of R is anoxygen-containing group, COOH is not present.

Also included are functionalized SWNTs and other carbon nanotubes havingthe formula (XXXV)[C_(n)H_(L)

R″—R]_(m)  (XXXIV)where n, L, m, R′ and R have the same meaning as above. Most carbonatoms in the surface layer of a carbon nanotube are basal plane carbons.Basal plane carbons are relatively inert to chemical attack. At defectsites, where, for example, the graphitic plane fails to extend fullyaround the carbon nanotube, there are carbon atoms analogous to the edgecarbon atoms of a graphite plane. The edge carbons are reactive and cancontain some heteroatom or group to satisfy carbon valency.

The substituted SWNTs and other carbon nanotubes described above mayadvantageously be further functionalized. Such compositions includecompositions of the formula (XXXV)[C_(n) H_(L)

A_(m)  (XXXV)where n, L and m are as described above, A is selected from —OY, —NHY,—CR′₂—OY, —C(O)OY, —C(O)NR′Y, —C(O)SY, or —C(O)Y, wherein Y is anappropriate functional group of a protein, a peptide, an enzyme, anantibody, a nucleotide, an oligonucleotide, an antigen, or an enzymesubstrate, enzyme inhibitor or the transition state analog of an enzymesubstrate or is selected from —R′OH, —R′NH₂ , —R′SH, —R′CHO, —R′CN,—R′X, —R′SiR′₃, —RSi—(OR′)_(y)—R′_((3-y)), —R′Si—(O—SiR′₂)—OR′, —R′—R″,—R′—NCO, (C₂H₄ O)_(w)Y, —(C₃H₆O)_(w)H, —(C₂H₄O)_(w)R′, —(C₃H₆O)_(w)R′and R″, wherein w is an integer greater than one and less than 200.

The functional SWNTs and other carbon nanotubes of structure (XXXIV) mayalso be functionalized to produce compositions having the formula(XXXVI)[C_(n)H_(L)

R′-A]_(m)  (XXXVI)where n, L, m, R′ and A are as defined above.

The compositions also include SWNTs and other carbon nanotubes uponwhich certain cyclic compounds are adsorbed. These include compositionsof matter of the formula (XXXVII)[C_(n)H_(L)

X—R_(a)]_(m)  (XXXVII)where n is an integer, L is a number less than 0.1 n, m is less than 0.5n, a is zero or a number less than 10, X is a polynuclear aromatic,polyheteronuclear aromatic or metallopolyheteronuclear aromatic moietyand R is as recited above. Preferred cyclic compounds are planarmacrocycles such as re porphyrins and phthalocyanines.

The adsorbed cyclic compounds may be functionalized. Such compositionsinclude compounds of the formula (XXXVIII)[C_(n)H_(L)

X-A_(a)]_(m)  (XXXVIII)where m, n, L, a, X and A are as defined above and the carbons are onthe SWNT or on other nanotubes such as MWNTs, VGCF, or the like.

Without being bound to a particular theory, the functionalized SWNTs andother carbon nanotubes are better dispersed into organic polymersbecause the modified surface properties may render the carbon nanotubemore compatible with the organic polymer, or, because the modifiedfunctional groups (particularly hydroxyl or amine groups) are bondeddirectly to the organic polymer as terminal groups. In this way, organicpolymers such as polycarbonates, polyamides, polyesters,polyetherimides, or the like, bond directly to the carbon nanotubes,thus making the carbon nanotubes easier to disperse with improvedadherence to the organic polymer.

Functional groups may generally be introduced onto the outer surface ofthe SWNTs and the other carbon nanotubes by contacting the respectiveouter surfaces with a strong oxidizing agent for a period of timesufficient to oxidize the surface of the SWNTs and other carbonnanotubes and further contacting the respective outer surfaces with areactant suitable for adding a functional group to the oxidized surface.Preferred oxidizing agents are comprised of a solution of an alkalimetal chlorate in a strong acid. Preferred alkali metal chlorates aresodium chlorate or potassium chlorate. A preferred strong acid used issulfuric acid. Periods of time sufficient for oxidation are about 0.5hours to about 24 hours.

Carbon black may also be optionally used in the compositions. Preferredcarbon blacks are those having average particle sizes less than about200 nm, preferably less than about 100 nm, more preferably less thanabout 50 nm. Preferred conductive carbon blacks may also have surfaceareas greater than about 200 square meter per gram (m²/g), preferablygreater than about 400 m²/g, yet more preferably greater than about 1000m²/g. Preferred conductive carbon blacks may have a pore volume (dibutylphthalate absorption) greater than about 40 cubic centimeters perhundred grams (cm³/100 g), preferably greater than about 100 cm³/100 g,more preferably greater than about 150 cm³/100 g. Exemplary carbonblacks include the carbon black commercially available from ColumbianChemicals under the trade name Conductex®; the acetylene black availablefrom Chevron Chemical, under the trade names S.C.F. (Super ConductiveFurnace) and E.C.F. (Electric Conductive Furnace); the carbon blacksavailable from Cabot Corp. under the trade names Vulcan XC72 and BlackPearls; and the carbon blacks commercially available from Akzo Co. Ltdunder the trade names Ketjen Black EC 300 and EC 600. Preferredconductive carbon blacks may be used in amounts from about 2 wt % toabout 25 wt % based on the total weight of the composition.

Solid conductive metallic fillers may also optionally be used in theconductive compositions. These may be electrically conductive metals oralloys that do not melt under conditions used in incorporating them intothe organic polymer, and fabricating finished articles therefrom. Metalssuch as aluminum, copper, magnesium, chromium, tin, nickel, silver,iron, titanium, and mixtures comprising any one of the foregoing metalscan be incorporated into the organic polymer as conductive fillers.Physical mixtures and true alloys such as stainless steels, bronzes, andthe like, may also serve as conductive filler particles. In addition, afew intermetallic chemical compounds such as borides, carbides, and thelike, of these metals, (e.g., titanium diboride) may also serve asconductive filler particles. Solid non-metallic, conductive fillerparticles such as tin-oxide, indium tin oxide, and the like may alsooptionally be added to render the organic polymer conductive. The solidmetallic and non-metallic conductive fillers may exist in the form ofpowder, drawn wires, strands, fibers, tubes, nanotubes, flakes,laminates, platelets, ellipsoids, discs, and other commerciallyavailable geometries.

Non-conductive, non-metallic fillers that have been coated over asubstantial portion of their surface with a coherent layer of solidconductive metal may also optionally be used in the conductivecompositions. The non-conductive, non-metallic fillers are commonlyreferred to as substrates, and substrates coated with a layer of solidconductive metal may be referred to as “metal coated fillers”. Typicalconductive metals such as aluminum, copper, magnesium, chromium, tin,nickel, silver, iron, titanium, and mixtures comprising any one of theforegoing metals may be used to coat the substrates. Examples ofsubstrates include those described in “Plastic Additives Handbook,5^(th) Edition” Hans Zweifel, Ed, Carl Hanser Verlag Publishers, Munich,2001. Examples of such substrates include silica powder, such as fusedsilica and crystalline silica, boron-nitride powder, boron-silicatepowders, alumina, magnesium oxide (or magnesia), wollastonite, includingsurface-treated wollastonite, calcium sulfate (as its anhydride,dihydrate or trihydrate), calcium carbonate, including chalk, limestone,marble and synthetic, precipitated calcium carbonates, generally in theform of a ground particulates, talc, including fibrous, modular, needleshaped, and lamellar talc, glass spheres, both hollow and solid, kaolin,including hard, soft, calcined kaolin, and kaolin comprising variouscoatings to facilitate compatibility with the polymeric matrix polymer,mica, feldspar, silicate spheres, flue dust, cenospheres, fillite,aluminosilicate (armospheres), natural silica sand, quartz, quartzite,perlite, tripoli, diatomaceous earth, synthetic silica, and mixturescomprising any one of the foregoing. All of the above substrates may becoated with a layer of metallic material for use in the conductivecompositions.

Regardless of the exact size, shape and composition of the solidmetallic and non-metallic conductive filler particles, they may bedispersed into the organic polymer at loadings of about 0.001 to about50 wt % of the total weight of the composition when desired. Within thisrange it is generally desirable to have the solid metallic andnon-metallic conductive filler particles in an amount of greater than orequal to about 1 wt %, preferably greater than or equal to about 1.5 wt% and more preferably greater than or equal to about 2 wt % of the totalweight of the composition. The loadings of the solid metallic andnon-metallic conductive filler particles may be less than or equal to 40wt %, preferably less than or equal to about 30 wt %, more preferablyless than or equal to about 25 wt % of the total weight of thecomposition.

In one embodiment, in one method of manufacturing the composition, thepolymeric precursor in the form of a monomer, oligomer, or polymer isadded to a reaction vessel. Suitable examples of reaction vessels arekettles, thin film evaporators, single or multiple screw extruders, Busskneaders, Henschel mixers, helicones, Ross mixers, Banbury, roll mills,molding machines such as injection molding machines, vacuum formingmachines, blow molding machine, or then like, or combinations comprisingat least one of the foregoing machines. The conductive compositioncomprising the SWNTs and optionally other carbon nanotubes andconductive fillers may then be added to the reaction vessel during thepolymerization of the polymeric precursor.

In one embodiment, the SWNTs may be added to the reaction vessel priorto the polymerization of the polymer precursor. The polymerization ofthe polymer precursor may be conducted in a solvent or in the absence ofa solvent, in the melt if desired. In another embodiment, the SWNTs maybe added to the reaction vessel during the polymerization of the polymerprecursor. In yet another embodiment, the SWNTs may be added to thereaction vessel prior the polymerization of the polymer precursor, whilethe other conductive and non-conductive fillers may be added to thereaction vessel after the polymerization of the organic precursors issubstantially completed. In yet another embodiment, the reaction vesselmay contain a high proportion of the SWNTs and other conductive andnon-conductive fillers during the initial stages of the polymerizationprocess in order to adjust the viscosity in the reaction to vessel to beeffective to facilitate the disentangling of the SWNTs and otherfillers. After agitating the reaction solution for a desired period oftime, additional polymer precursors are added to the reaction vessel tocontinue the polymerization process.

In one embodiment, the SWNTs together with other conductive andnon-conductive fillers may be added to the reaction vessel in the formof a masterbatch. In another embodiment, related to the use ofmasterbatches, a first masterbatch comprising the SWNTs may be added tothe reaction vessel at a first time, while the second masterbatchcomprising the other non-conductive fillers may be added to the reactionvessel at a second time during the process of polymerization of thepolymer precursors.

As stated above, the composition may be manufactured in the melt or in asolution comprising a solvent. Melt reacting of the composition involvesthe use of shear force, extensional force, compressive force, ultrasonicenergy, electromagnetic energy, thermal energy or combinationscomprising at least one of the foregoing forces or forms of energy andis conducted in processing equipment wherein the aforementioned forcesare exerted by a single screw, multiple screws, intermeshing co-rotatingor counter rotating screws, non-intermeshing co-rotating or counterrotating screws, reciprocating screws, screws with pins, screws withscreens, barrels with pins, rolls, rams, helical rotors, baffles, orcombinations comprising at least one of the foregoing.

In one embodiment, ultrasonic energy may be utilized to disperse theSWNTs. The polymer precursors together with the SWNTs, and otheroptional conductive or non-conductive fillers are first sonicated in anultrasonicator to disperse the SWNTs. Following the sonication, thepolymer precursors are polymerized. The ultrasonication may be continuedduring the polymerization process if desired. The ultrasonic energy maybe applied to the different reaction vessels such as kettles, extruders,and the like, in which the polymerization may be carried out.

Melt reacting involving the aforementioned forces may be conducted inmachines such as, but not limited to single or multiple screw extruders,Buss kneader, Henschel, helicones, Ross mixer, Banbury, roll mills,molding machines such as injection molding machines, vacuum formingmachines, blow molding machine, or then like, or combinations comprisingat least one of the foregoing machines. Solution reacting is generallyconducted in a vessel such as a kettle.

In one embodiment, the polymer precursor in powder form, pellet form,sheet form, or the like, may be first dry blended with the SWNTs andother optional fillers if desired in a Henschel or a roll mill, prior tobeing fed into a reaction vessel such as an extruder or Buss kneader.While it is generally desirable for the shear forces in the reactionvessel to generally cause a dispersion of the SWNTs in the polymerprecursor, it is also desired to preserve the aspect ratio of the SWNTsduring the reaction. In order to do so, it may be desirable to introducethe SWNTs into the reaction vessel in the form of a masterbatch. In sucha process, the masterbatch may be introduced into the reaction vesseldownstream of the polymer precursor.

The masterbatch may comprise either an organic polymer or a polymerprecursor with the SWNTs. When a masterbatch is used, the SWNTs may bepresent in the masterbatch in an amount of about 0.01 to about 50 wt %.Within this range, it is generally desirable to use SWNTs in an amountof greater than or equal to about 0.1 wt %, preferably greater or equalto about 0.2 wt %, more preferably greater than or equal to about 0.5 wt% of the total weight of the masterbatch. Also desirable are SWNTs in anamount of less than or equal to about 30 wt %, preferably less than orequal to about 10 wt %, more preferably less than or equal to about 5 wt% of the total weight of the masterbatch. In one embodiment pertainingto the use of masterbatches, while the masterbatch containing the SWNTsmay not have a measurable bulk or surface resistivity either whenextruded in the form of a strand or molded into the form of dogbone, theresulting composition into which the masterbatch is incorporated has ameasurable bulk or surface resistivity, even though the weight fractionof the SWNTs in the composition is lower than that in the masterbatch.It is preferable for the organic polymer in such a masterbatch to besemi-crystalline. Examples of semi-crystalline organic polymers whichdisplay these characteristics and which may be used in masterbatches arepolypropylene, polyamides, polyesters, or the like, or combinationscomprising at least on of the foregoing semi-crystalline organicpolymers.

The composition may also be used as a masterbatch if desired. When thecomposition is used as a masterbatch, the SWNTs may be present in themasterbatch in an amount of about 0.01 to about 50 wt %. Within thisrange, it is generally desirable to use SWNTs in an amount of greaterthan or equal to about 0.1 wt %, preferably greater or equal to about0.2 wt %, more preferably greater than or equal to about 0.5 wt % of thetotal weight of the masterbatch. Also desirable are SWNTs in an amountof less than or equal to about 30 wt %, preferably less than or equal toabout 10 wt %, more preferably less than or equal to about 5 wt % of thetotal weight of the masterbatch.

In another embodiment relating to the use of masterbatches in themanufacture of a composition comprising a blend of organic polymers, itis sometimes desirable to have the masterbatch comprising an organicpolymer that is the same as the organic polymer that is derived from thepolymerization of the polymer precursors. This feature permits the useof substantially smaller proportions of the SWNTs, since only thecontinuous phase of the organic polymer carries the SWNTs that providethe composition with the requisite volume and surface resistivity. Inyet another embodiment relating to the use of masterbatches in polymericblends, it may be desirable to have the masterbatch comprising anorganic polymer that is different in chemistry from other the polymericthat are used in the composition. In this case, the organic polymer ofthe masterbatch will form the continuous phase in the blend. In yetanother embodiment, it may be desirable to use a separate masterbatchcomprising multiwall nanotubes, vapor grown carbon fibers, carbon black,conductive metallic fillers, solid non-metallic, conductive fillers, orthe like, or combinations comprising at least one of the foregoing inthe composition.

The composition comprising the organic polymer and the SWNTs may besubject to multiple blending and forming steps if desirable. Forexample, the composition may first be extruded and formed into pellets.The pellets may then be fed into a molding machine where it may beformed into other desirable shapes such as housing for computers,automotive panels that can be electrostatically painted, or the like.Alternatively, the composition emanating from a single melt blender maybe formed into sheets or strands and subjected to post-extrusionprocesses such as annealing, uniaxial or biaxial orientation.

In one embodiment, the organic polymer precursor may be first mixed withthe SWNT's in a reaction vessel such as a kettle, and subsequentlypolymerized in a device where a combination of shear, extension and/orelongational forces are used during the polymerization. Suitable devicesfor conducting the polymerization are those having a single screw,multiple screws, intermeshing co-rotating or counter rotating screws,non-intermeshing co-rotating or counter rotating screws, reciprocatingscrews, screws with pins, screws with screens, barrels with pins, rolls,rams, helical rotors, baffles, or combinations comprising at least oneof the foregoing.

Solution blending may also be used to manufacture the composition. Thesolution blending may also use additional energy such as shear,compression, ultrasonic vibration, or the like, to promotehomogenization of the SWNTs with the organic polymer. In one embodiment,the polymer precursors may be introduced into an ultrasonic sonicatoralong with the SWNTs. The mixture may be solution blended by sonicationfor a time period effective to disperse the SWNTs onto the organicpolymer particles prior to or during synthesis of the polymerprecursors. The organic polymer along with the SWNTs may then be dried,extruded and molded if desired.

A fluid such as a solvent may optionally be introduced into thesonicator with the SWNTs and the organic polymer precursor. The timeperiod for the sonication is generally an amount effective to promotedispersion and/or encapsulation of the SWNTs by the organic polymerprecursor. After the encapsulation, the organic polymer precursor isthen polymerized to form an organic polymer within which is dispersedthe SWNTs. This method of dispersion of the SWNTs in the organic polymerpromotes the preservation of the aspect ratios of the SWNTs, whichtherefore permits the composition to develop electrical conductivity atlower loading of the SWNTs.

In general, it is desirable to sonicate the mixture of organic polymer,organic polymer precursor, fluid and the SWNTs a period of about 1minute to about 24 hours. Within this range, it is desirable to sonicatethe mixture for a period of greater than or equal to about 5 minutes,preferably greater than or equal to about 10 minutes and more preferablygreater than or equal to about 15 minutes. Also desirable within thisrange is a time period of less than or equal to about 15 hours,preferably less than or equal to about 10 hours, and more preferablyless than or equal to about 5 hours.

In one embodiment, after sonication, the mixture of organic polymerand/or organic polymer precursor, fluid and the SWNTs is allowed to stayunperturbed in the sonication vessel for a period of about 5 minutes toabout 24 hours. By allowing the mixture to stay unperturbed for anextended period of time, the carbon nanotubes undergo reorganization toform a percolating network in the organic polymer or in the organicpolymer precursor. The strength of electrical conductivity in theconducting composition can be related to the amount of time for whichthe mixture is left unperturbed. In an exemplary embodiment, the mixtureafter sonication can be left unperturbed for a period of about 15minutes to about 12 hours. After being left unperturbed for a period oftime, the mixture can be subjected to polymerization.

If the solution blending is conducted in a vessel with a stirrer, thenit is desirable to stir the mixture as slowly as possible. Stirring themixture at a low shear rate during solution blending and/orpolymerization facilitates disentangling of the single wall carbonnanotubes and the formation of a percolating network in the conductingcomposite. In one embodiment, during the solution blending it isdesirable to subject the mixture to a shear rate of less than or equalto about 100 seconds⁻¹. In another embodiment, during the solutionblending it is desirable to subject the mixture to a shear rate of lessthan or equal to about 50 seconds⁻¹. In yet another embodiment, duringthe solution blending it is desirable to subject the mixture to a shearrate of less than or equal to about 20 seconds⁻¹. In yet anotherembodiment, during the solution blending it is desirable to subject themixture to a shear rate of less than or equal to about 10 seconds⁻¹.

In another embodiment, annealing the conductive composition afterpolymerization can cause an improvement in electrical conductivity. Inone embodiment, the conductive composition can be annealed at atemperature above the glass transition temperature of the polymer for aperiod of up to 12 hours. In another embodiment, the conductivecomposition can be advantageously annealed at a temperature ofT_(g)+/−50° C., where T_(g) is the glass transition temperature of thepolymer. In yet another embodiment, the conductive composition can beannealed above the melting point of the polymer. Annealing theconductive composition produces an increase in electrical conductivityof greater than or equal to about 10% over an identical composition thathas not been annealed.

In one embodiment, related to the dispersion of the SWNTs havingproduction related impurities, the SWNT compositions having a higherfraction of impurities may be dispersed using less energy than SWNTcompositions having a lower fraction of impurities. Without beinglimited by theory, it is believed that in certain organic polymers, theimpurities interact to promote a reduction in the Van der Waal's forcesthereby facilitating an easier dispersion of the nanotubes within theorganic polymer.

In another embodiment, related to the dispersion of SWNTs havingproduction related impurities, the SWNT compositions having a higherfraction of impurities may require a larger amount of mixing than thosecompositions having a lower fraction of impurities. However, thecomposition having the SWNTs with the lower fraction of impuritiesgenerally lose electrical conductivity upon additional mixing, while thecomposition having the higher fraction of SWNT impurities generally gainin electrical conductivity as the amount of mixing is increased. Thesecompositions may be used in applications where there is a need for asuperior balance of flow, impact, and conductivity. They may also beused in applications where conductive materials are used and wherein theconductive materials possess very small levels of conductive filler suchas in fuel cells, electrostatic painting applications, and the like.

The compositions described above may be used in a wide variety ofcommercial applications. They may be advantageously utilized as filmsfor packaging electronic components such as computers, electronic goods,semi-conductor components, circuit boards, or the like that need to beprotected from electrostatic dissipation. They may also be usedinternally inside computers and other electronic goods to provideelectromagnetic shielding to personnel and other electronics locatedoutside the computer as well as to protect internal computer componentsfrom other external electromagnetic interference. They may also be usedadvantageously in automotive body panels both for interior and exteriorcomponents of automobiles that can be electrostatically painted ifdesired.

The following examples, which are meant to be exemplary, not limiting,illustrate compositions and methods of manufacturing of some of thevarious embodiments of the electrically conductive compositionsdescribed herein.

EXAMPLES Example 1

This example was undertaken to disperse SWNTs in polycarbonate (PC) andto create a masterbatch of SWNTs in PC. 250 milligrams (mg) of SWNTsobtained from Carbon Nanotechnologies Incorporated was first dispersedin 120 milliliter (ml) of 1,2 dichloroethane by using an ultrasonicationhorn for 30 minutes. The ultrasonic horn used an ultrasonic processor at80% amplitude (600 Watts, probe diameter of 13 mm available from Sonics& Materials Incorporated). 30 gms of bis(methylsalicyl)carbonate (BMSC)and 20.3467 gms of bisphenol A (BPA) (mol of BMSC/mol of BPA=1.02) wereadded to dispersion and SWNT the reaction mixture was again sonicatedfor 30 minutes. The sonicated mass was transferred into a glass reactor,which was first passivated by soaking the reactor in a bath containing 1molar aqueous hydrochloric acid solution for 24 hours followed byvigorous rinsing with deionized water. The solvent was dried by heatingthe glass reactor to 100° C. in presence of flowing nitrogen at lowpressure. Appropriate amount of catalyst solution was then introducedinto the reactor using a syringe. The amount of catalyst consists of4.5×10⁻⁶ moles of NaOH per mole of BPA and 3.0×10⁻⁴ moles of TBPA(tetrabutyl phosphonium acetate) per mole of BPA (bisphenol A).

The atmosphere inside the reactor was then evacuated using a vacuumsource and purged with nitrogen. This cycle was repeated 3 times afterwhich the contents of the reactor were heated to melt the monomermixture (bis(methylsalicyl)carbonate (BMSC) and bisphenol A (BPA)). Whenthe temperature of the mixture reached about 180° C., the stirrer in thereactor was turned on and adjusted to about 60 revolutions per minute(rpm) to ensure that the entire solid mass fully melted, a process thatusually took about 15 to about 20 minutes. Next, the reaction mixturewas heated to about 220° C., while the pressure inside the reactor wasadjusted slowly to about 100 millibar using a vacuum source. Afterstirring the reaction mass at this condition for about 15 minutes, thereaction temperature was raised to about 280° C. while readjusting thepressure to around 20 millibar. After being maintained at this conditionfor about 10 minutes, the temperature of the reaction mixture was raisedto 300° C. while bringing the pressure down to about 1.5 millibar. Afterallowing the reaction to proceed under these conditions for about 2 toabout 5 minutes, the pressure inside the reactor was brought toatmospheric pressure and the reactor was vented to relieve any excesspressure. Product isolation was accomplished by breaking the glassnipple at the bottom of the reactor and collecting the material. Theglass reactor was dismantled and the rest of the polymer was taken ourfrom the reactor tube.

To measure the molecular weight, the resulting polycarbonate wasdissolved in methylene chloride followed by re-precipitation of thepolymers from methanol. The molecular weight of the polymer wasdetermined by gel permeation chromatography with respect to polystyrenestandard. The weight average molecular weight was 55756 g/mole, whilethe number average molecular weight was 23,938 g/mole and thepolydispersity index was 2.32.

Example 2

This example was undertaken to disperse SWNTs in PCCD(poly(1,4-cyclohexane-dimethanol-1,4-cyclohexanedicarboxylate)polymerand to create a masterbatch of SWNTs in PCCD. The PCCD polymer wassynthesized by melt polycondensation in presence of SWNTs obtained fromCarbon Nanotechnologies Incorporated. A slurry of SWNTs (0.24 gm, 1 wt%) was prepared by mixing the SWNTs with 1,4-dimethyl cyclohexanedicarboxylate (14.01 gm, 0.07 moles) (DMCD), 1,4-cyclohexane dimethanol(10.09 gm, 0.07 moles) (CHDM) and 1,2-dichloroethane (50 mL) undersonication as described in example 1. The slurry was transferred to theglass reactor tube. The reactor tube was mounted to the meltpolycondensation reactor equipped with side arm, a mechanical stirrerdriven by an overhead stirring motor and a side arm with a stop-cock.The side arm is used to purge nitrogen gas as well as for applyingvacuum. Initially, the reactor tube was heated under nitrogen to removethe 1,2-dichloroethane and cooled to room temperature. The contents inthe reactor were evacuated and purged with nitrogen three times toremove any traces of oxygen. The reactor was purged with nitrogen andbrought to atmospheric pressure and the contents of the reaction mixturewere heated to 200° C. with constant stirring (100 rpm). Through theside arm 400 parts per million (ppm) of titanium (IV) isopropoxide wasadded as a catalyst and the ester interchange reaction proceeded withthe distillation of methanol which was collected through the side arm inthe measuring cylinder (receiver). The temperature of the melt wasincreased to 250 ° C. and stirred for 1 hour under nitrogen. Thepolycondensation was conducted by reducing the pressure in the reactorin stepwise from 900 mm Hg to 700, 500, 300, 100, 50, 25, and 10 mmmercury (Hg). Finally, a full vacuum of 0.5 to 0.1 mbar was applied tothe reactor and the polymerization was continued for 30 minutes. Aftercompletion of the polymerization, the pressure inside the reactor wasbrought to atmospheric pressure by purging with nitrogen and the polymercomposite was removed from the reactor tube. The polymer was dissolvedin dichloromethane for molecular weight determinations using theintrinsic viscosity method. The solution viscosity was determined inphenol/tetrachloroethane (a volume ratio of 2:3 at 25° C.) solution andwas found to be 0.58 deciliter/gram (dL/g), which corresponds to theviscosity average molecular weight of 50,000 g/mole.

The masterbatches prepared in Examples 1 and 2 were then melt blendedwith polymers in a small scale laboratory mixing and molding machine todecrease the loading or the SWNT. The strands from the molding machinewere fractured under liquid nitrogen and the exposed ends were paintedwith conductive silver paint to make the conductivity measurements. Theconductivity values are shown in the Table 1 below.

TABLE 1 Sample # Final Composition Resistivity (kOhm-cm) 1 1.1 wt % SWNTin PC 3.5 2 0.5 wt % SWNT in PC 49 3 0.3 wt % SWNT in PC 119 4 0.2 wt %SWNT in PC 18,500 5 1.1 wt % SWNT in PCCD 17.5 6 0.5 wt % SWNT in PCCD76 7 0.3 wt % SWNT in PCCD 1,100 8 0.5 wt % SWNT in PCCD/PC 10.0 (50/50by weight) 9 0.3 wt % SWNT in PCCD/PC 275 (30/70 by weight)

As may be seen from the above table, Samples 2-4 were manufactured fromPC masterbatches of Example 1 (sample # 1), while Samples 6-9 weremanufactured from the masterbatches of Example 2 (sample# 5). From theExamples it can be clearly seen that as the level of the SWNTs isincreased, the resistivity is decreased. Further it can be seen that themasterbatches may be advantageously used to disperse the SWNT's in thepolymer.

Example 3

This example was used to prepared a masterbatch of SWNTs in Nylon 6during the polymerization of the polyamide. 24.8 gm of ε-caprolactam wastaken in a beaker and heated to 90° C. After compound has melted, 250milligrams (mg) of SWNTs containing about 10 wt % impurities(commercially available from Carbon Nanotechnologies Incorporated) wasadded to the ε-caprolactam. The mixture was ultrasonicated at the sametemperture for half an hour using an ultrasonic processor at 80%amplitude (600 Watts, probe diameter of 13 mm available from Sonics &Materials Incorporated). The dispersion of SWNTs in the moltenε-caprolactam was then transferred to a reactor tube and was keptovernight to allow the SWNT ropes to gel (forming a network). 1.5 gm ofaminocaproic acid was then added to the reactor and caprolactam waspolymerized to nylon-6 by ring-opening polymerization, under nitrogenwith slow stirring, for 9 hours at 260° C.

Example 4

This experiment was undertaken to prepare an SWNT composite in PCCD byin-situ polymerization without using a solvent. In this example, 17.29gm of 1,4-cyclohexane dicarboxylate, 24.03 gms of 1,4-cyclohexanedimethanol was mixed and melted at 80° C. in a beaker. 33 mg of SWNTcontaining about 10 wt % impurities (commercially available from CarbonNanotechnologies Incorporated) was added to the beaker. The mixture wasultrasonicated at the same temperture for half an hour using anultrasonic processor at 80% amplitude (600 Watts, probe diameter 13 mm,Sonics & Materials Incorporated, USA). The dispersion of SWNT in themolten monomer mixture was then transferred to a reactor tube and waskept overnight to allow the SWNT ropes to gel (forming a network). Themonomers were then polymerized to PCCD using the same procedure as inExample 2.

A portion of the composite prepared above was heated for one hour to240° C. for Nylon 6 composite of Example 3 (above the melting point ofNylon 6) and 230° C. for the PCCD composite of Example 4 respectively.The composite was then cooled slowly to room temperature and theconductivity was measured as shown in Table 2. Similarly, the compositematerial from Examples 3 and 4 was melted mixed with additional polymerand pressed through in a small scale laboratory mixing and moldingmachine to form strands which were then used to make conductivitymeasurements as detailed in Example 2. These results are also shown inTable 4.

TABLE 4 Resistivity (kOhm-cm) Sample # Final Composition (S.D.*) 10 0.1wt % SWNT in PCCD of — Example 4 11 0.1 wt % SWNT in PCCD of 10,030Example 4 (with annealing) 12 1 wt % SWNT in Nylon 6 of 33 (13) Example3 13 1 wt % SWNT in Nylon 6 of 24 (14) Example 3 (with annealing) 14 0.5wt % SWNT in Nylon 6 14715 (3986) (melt mixing; sample #12 used asmasterbatch) 15 0.5 wt % SWNT in Nylon 6 4075 (2390) (melt mixing usingsample #13 as masterbatch) 16 0.5 wt % SWNT in Nylon 6 702 (melt mixedand annealed in the mold) *S.D. represents the numbers in theparenthesis, which are the standard deviations.

From the above data it may be seen that the samples that were annealeddisplayed superior electrical properties than those samples that wereannealed. Annealing enables the SWNT ropes to rearrange in the polymermatrix and increases the rejoining/sharing of the SWNT rope-branches,creating an extensive long range networked morphology, which in turn,leads to higher conductivity of the composites.

While the invention has been described with reference to exemplaryembodiments, it will be understood by those skilled in the art thatvarious changes may be made and equivalents may be substituted forelements thereof without departing from the scope of the invention. Inaddition, many modifications may be made to adapt a particular situationor material to the teachings of the invention without departing from theessential scope thereof. Therefore, it is intended that the inventionnot be limited to the particular embodiment disclosed as the best modecontemplated for carrying out this invention.

1. A method for manufacturing a conductive composition comprising:blending a polymer precursor with a single wall carbon nanotubecomposition, the single wall nanotube composition comprising carbonnanotubes that have a single wall; and polymerizing the polymerprecursor to form an organic polymer; and wherein the composition has anelectrical bulk volume resistivity less than or equal to about 10¹²ohm-cm, and a notched Izod impact strength greater than or equal toabout 5 kilojoules/square meter.
 2. The method of claim 1 wherein thecomposition has an electrical surface resistivity less than or equal toabout 10¹² ohm/square.
 3. The method of claim 1, wherein the organicpolymer is a polyacetal, a polyacrylic, a polyalkyd, a polyacrylate, apolycarbonate, a polystyrene, a polyester, a polyamide, a polyaramid, apolyamideimide, a polyarylate, a polyarylsulfone, a polyethersulfone, apolyphenylene sulfide, a polysulfone, a polyimide, a polyetherimide, apolytetrafluoroethylene, a polyetherketone, a polyether etherketone, apolyether ketone ketone, a polybenzoxazole, a polyoxadiazole, apolybenzothiazinophenothiazine, a polybenzothiazole, apolypyrazinoquinoxaline, a polypyromellitimide, a polyquinoxaline, apolybenzimidazole, a polyoxindole, a polyoxoisoindoline, apolydioxoisoindoline, a polytriazine, a polypyridazine, apolypiperazine, a polypyridine, a polypiperidine, a polytriazole, apolypyrazole, a polycarborane, a polyoxabicyclononane, apolydibenzofuran, a polyphthalide, a polyacetal, a polyanhydride, apolyvinyl ether, a polyvinyl thioether, a polyvinyl alcohol, a polyvinylketone, a polyvinyl halide, a polyvinyl nitrile, a polyvinyl ester, apolysulfonate, a polysulfide, a polythioester, a polysulfone, apolysulfonamide, a polyurea, a polyphosphazene, a polysilazane, or acombination comprising at least one of the foregoing thermoplasticpolymers.
 4. T he method of claim 1, further comprising carbonnanotubes, wherein the carbon nanotubes are multiwall carbon nanotubes,vapor grown carbon fibers, or a combination comprising at least one ofthe foregoing types of carbon nanotubes; the multiwall carbon nanotubesand the vapor grown carbon fibers comprise carbon nanotubes that have atleast two graphene layers.
 5. The method of claim 1, wherein the singlewall carbon nanotube composition comprises about 30 to about 99 wt %metallic carbon nanotubes.
 6. The method of claim 1, wherein the singlewall carbon nanotube composition comprises about 30 to about 99 wt %semi-conducting carbon nanotubes.
 7. The method of claim 1, wherein atleast a portion of the single wall carbon nanotube composition isderivatized with functional groups.
 8. The method of claim 1, whereinthe single wall carbon nanotube composition comprises at least a portionof single wall carbon nanotubes derivatized with functional groupseither on a side-wall or on a hemispherical end.
 9. The method of claim1, wherein the single wall carbon nanotube composition comprises atleast a portion of single wall carbon nanotubes having no hemisphericalends attached thereto or has a single hemispherical end attachedthereto.
 10. The method of claim 1, wherein the blending is accomplishedthrough sonicating.
 11. The method of claim 10, further comprisingadding a solvent prior to sonication.
 12. The method of claim 1, whereinthe blending is accomplished in a solution comprising a solvent.
 13. Themethod of claim 1, wherein the blending is accomplished in a melt. 14.The method of claim 1, wherein the composition is used as a masterbatch.15. The method of claim 1, wherein the blending involves the use ofshear force, extensional force, compressive force, ultrasonic energy,electromagnetic energy, thermal energy or combinations comprising atleast one of the foregoing forces and energies and is conducted inprocessing equipment wherein the aforementioned forces or energies areexerted by a single screw, multiple screws, intermeshing co-rotating orcounter rotating screws, non-intermeshing co-rotating or counterrotating screws, reciprocating screws, screws with pins, barrels withpins, screen packs, rolls, rams, helical rotors, baffles, ultrasonicatoror combinations comprising at least one of the foregoing.
 16. The methodof claim 1, wherein the blending is conducted in a kettle, while thepolymerization is conducted in a device having a single screw, multiplescrews, intermeshing co-rotating or counter rotating screws,non-intermeshing co-rotating or counter rotating screws, reciprocatingscrews, screws with pins, screws with screens, barrels with pins, rolls,rams, helical rotors, baffles, or a combination comprising at least oneof the foregoing.
 17. An article manufactured by the method of claim 1.18. A method for manufacturing a conductive composition comprising:blending a polymer precursor with a single wall carbon nanotubecomposition, the single wall nanotube composition comprising carbonnanotubes that have a single wall; and polymerizing the polymerprecursor to form an organic polymer; wherein the composition has anelectrical bulk volume resistivity less than or equal to about 10¹²ohm-cm, and a notched Izod impact strength greater than or equal toabout 5 kilojoules/square meter, and wherein the composition has a ClassA surface finish.
 19. The method of claim 18, wherein the single wallcarbon nanotube composition comprises about 30 to about 99 wt % metalliccarbon nanotubes.
 20. The method of claim 18, wherein the single wallcarbon nanotube composition comprises about 50 to about 99 wt % metalliccarbon nanotubes.
 21. The method of claim 18, wherein the single wallcarbon nanotube composition comprises about 30 to about 99 wt %semi-conducting carbon nanotubes.
 22. The method of claim 18, whereinthe single wall carbon nanotube composition comprises about 50 to about99 wt % semi-conducting carbon nanotubes.
 23. The method of claim 18,wherein the blending is conducted at a shear rate of less than or equalto about 100 seconds⁻¹.
 24. The method of claim 18, wherein the blendingis conducted at a shear rate of less than or equal to about 10seconds⁻¹.
 25. The method of claim 18, further comprising leaving theconductive composition in an unperturbed state for up to 24 hours afterblending.
 26. The method of claim 18, further comprising leaving theconductive composition in an unperturbed state for up to 24 hours afterpolymerizing the polymer precursor.
 27. The method of claim 18, furthercomprising annealing the conductive composition after polymerizing thepolymer precursor.
 28. The method of claim 18, further comprisingannealing the conductive composition at a temperature above the glasstransition temperature of the organic polymer.
 29. An articlemanufactured by the method of claim 18.